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proof-pile / formal /afp /BDD /ShareReduceRepListProof.thy
Zhangir Azerbayev
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(* Title: BDD
Author: Veronika Ortner and Norbert Schirmer, 2004
Maintainer: Norbert Schirmer, norbert.schirmer at web de
License: LGPL
*)
(*
ShareReduceRepListProof.thy
Copyright (C) 2004 Veronika Ortner and Norbert Schirmer
Some rights reserved, TU Muenchen
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA
*)
section \<open>Proof of Procedure ShareReduceRepList\<close>
theory ShareReduceRepListProof imports ShareRepProof begin
lemma (in ShareReduceRepList_impl) ShareReduceRepList_modifies:
shows "\<forall>\<sigma>. \<Gamma>\<turnstile>{\<sigma>} PROC ShareReduceRepList (\<acute>nodeslist)
{t. t may_only_modify_globals \<sigma> in [rep]}"
apply (hoare_rule HoarePartial.ProcRec1)
apply (vcg spec=modifies)
done
lemma hd_filter_app: "\<lbrakk>filter P xs \<noteq> []; zs=xs@ys\<rbrakk> \<Longrightarrow>
hd (filter P zs) = hd (filter P xs)"
by (induct xs arbitrary: n m) auto
lemma (in ShareReduceRepList_impl) ShareReduceRepList_spec_total:
defines "var_eq \<equiv> (\<lambda>ns var. (\<forall>no1 \<in> set ns. \<forall>no2 \<in> set ns. no1\<rightarrow>var = no2\<rightarrow>var))"
shows
"\<forall>\<sigma> ns. \<Gamma>\<turnstile>\<^sub>t
\<lbrace>\<sigma>. List \<acute>nodeslist \<acute>next ns \<and>
(\<forall>no \<in> set ns.
no \<noteq> Null \<and> ((no\<rightarrow>\<acute>low = Null) = (no\<rightarrow>\<acute>high = Null)) \<and>
no\<rightarrow>\<acute>low \<notin> set ns \<and> no\<rightarrow>\<acute>high \<notin> set ns \<and>
(isLeaf_pt no \<acute>low \<acute>high = (no\<rightarrow>\<acute>var \<le> 1)) \<and>
(no\<rightarrow>\<acute>low \<noteq> Null \<longrightarrow> (no\<rightarrow>\<acute>low)\<rightarrow>\<acute>rep \<noteq> Null) \<and>
((\<acute>rep \<propto> \<acute>low) no \<notin> set ns)) \<and>
var_eq ns \<acute>var\<rbrace>
PROC ShareReduceRepList (\<acute>nodeslist)
\<lbrace>(\<forall>no. no \<notin> set ns \<longrightarrow> no\<rightarrow>\<^bsup>\<sigma>\<^esup>rep = no\<rightarrow>\<acute>rep) \<and>
(\<forall>no \<in> set ns. no\<rightarrow>\<acute>rep \<noteq> Null \<and>
(if ((\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no \<and> no\<rightarrow> \<^bsup>\<sigma>\<^esup>low \<noteq> Null)
then (no\<rightarrow>\<acute>rep = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no )
else ((no\<rightarrow>\<acute>rep) \<in> set ns \<and> no\<rightarrow>\<acute>rep\<rightarrow>\<acute>rep = no\<rightarrow>\<acute>rep \<and>
(\<forall> no1 \<in> set ns.
((\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no1 = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no \<and>
(\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no1 = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no) = (no\<rightarrow>\<acute>rep = no1\<rightarrow>\<acute>rep)))))\<rbrace>"
apply (hoare_rule HoareTotal.ProcNoRec1)
apply (hoare_rule anno=
" \<acute>node :== \<acute>nodeslist;;
WHILE (\<acute>node \<noteq> Null )
INV \<lbrace>\<exists>prx sfx. List \<acute>node \<acute>next sfx \<and>
List \<acute>nodeslist \<acute>next ns \<and> ns=prx@sfx \<and>
(\<forall>no \<in> set ns.
no \<noteq> Null \<and> ((no\<rightarrow>\<^bsup>\<sigma>\<^esup>low = Null) = (no\<rightarrow>\<^bsup>\<sigma>\<^esup>high = Null)) \<and>
no\<rightarrow>\<^bsup>\<sigma>\<^esup>low \<notin> set ns \<and> no\<rightarrow>\<^bsup>\<sigma>\<^esup>high \<notin> set ns \<and>
(isLeaf_pt no \<^bsup>\<sigma>\<^esup>low \<^bsup>\<sigma>\<^esup>high = (no\<rightarrow>\<^bsup>\<sigma>\<^esup>var \<le> 1)) \<and>
(no\<rightarrow>\<^bsup>\<sigma>\<^esup>low \<noteq> Null \<longrightarrow> (no\<rightarrow>\<^bsup>\<sigma>\<^esup>low)\<rightarrow>\<^bsup>\<sigma>\<^esup>rep \<noteq> Null) \<and>
((\<^bsup>\<sigma>\<^esup>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no \<notin> set ns)) \<and>
var_eq ns \<acute>var \<and>
(\<forall>no. no \<notin> set prx \<longrightarrow> no\<rightarrow>\<^bsup>\<sigma>\<^esup>rep = no \<rightarrow>\<acute>rep) \<and>
(\<forall> no \<in> set prx. no\<rightarrow>\<acute>rep \<noteq> Null \<and>
(if ((\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no \<and> no\<rightarrow>\<^bsup>\<sigma>\<^esup>low \<noteq> Null)
then (no\<rightarrow>\<acute>rep = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no )
else ((no\<rightarrow>\<acute>rep)=hd (filter (\<lambda>sn. repNodes_eq sn no \<^bsup>\<sigma>\<^esup>low \<^bsup>\<sigma>\<^esup>high \<acute>rep)
prx) \<and>
((no\<rightarrow>\<acute>rep)\<rightarrow>\<acute>rep) = no\<rightarrow>\<acute>rep \<and>
(\<forall>no1 \<in> set prx.
((\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no1 = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>high) no \<and>
(\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no1 = (\<acute>rep \<propto> \<^bsup>\<sigma>\<^esup>low) no) =
(no\<rightarrow>\<acute>rep = no1\<rightarrow>\<acute>rep))))) \<and>
\<acute>nodeslist= \<^bsup>\<sigma>\<^esup>nodeslist \<and> \<acute>high=\<^bsup>\<sigma>\<^esup>high \<and> \<acute>low=\<^bsup>\<sigma>\<^esup>low \<and> \<acute>var=\<^bsup>\<sigma>\<^esup>var\<rbrace>
VAR MEASURE (length (list \<acute>node \<acute>next))
DO
IF (\<not> isLeaf_pt \<acute>node \<acute>low \<acute>high \<and>
\<acute>node \<rightarrow> \<acute>low \<rightarrow> \<acute>rep = \<acute>node \<rightarrow> \<acute>high \<rightarrow> \<acute>rep )
THEN \<acute>node \<rightarrow> \<acute>rep :== \<acute>node \<rightarrow> \<acute>low \<rightarrow> \<acute>rep
ELSE CALL ShareRep (\<acute>nodeslist , \<acute>node)
FI;;
\<acute>node :==\<acute>node \<rightarrow> \<acute>next
OD" in HoareTotal.annotateI)
apply (vcg spec=spec_total)
apply (rule_tac x="[]" in exI)
apply (rule_tac x="ns" in exI)
using [[simp_depth_limit = 2]]
apply (simp (no_asm_use))
prefer 2
using [[simp_depth_limit = 4]]
apply (clarsimp)
prefer 2
apply (rule conjI)
apply clarify
apply (rule conjI)
apply (clarsimp simp add: List_list) (* termination *)
apply (simp only: List_not_Null simp_thms triv_forall_equality)
apply clarify
apply (simp only: triv_forall_equality)
apply (rename_tac sfx)
apply (rule_tac x="prx@[node]" in exI)
apply (rule_tac x="sfx" in exI)
apply (rule conjI)
apply assumption
apply (rule conjI)
apply (simp (no_asm))
apply (rule conjI)
apply (assumption)
prefer 2
apply clarify
apply (simp only: List_not_Null simp_thms triv_forall_equality)
apply clarify
apply (simp only: triv_forall_equality)
apply (rename_tac sfx)
apply (rule_tac x="prx@node#sfx" in exI) (* Precondition for ShareRep *)
apply (rule conjI)
apply assumption
apply (rule conjI)
apply (rule ballI)
apply (frule_tac x=no in bspec, assumption)
apply (drule_tac x=node in bspec)
apply (simp (no_asm_use))
apply (elim conjE)
apply (rule conjI)
apply assumption
apply (rule conjI)
apply assumption
apply (unfold var_eq_def)
apply (drule_tac x=node in bspec, simp)
apply (drule_tac x=no in bspec,assumption)
apply (simp add: isLeaf_pt_def )
apply (rule conjI)
apply (simp (no_asm))
apply (clarify)
apply (rule conjI)
apply (subgoal_tac "List node next (node#sfx)") (* termination *)
apply (simp only: List_list)
apply (simp (no_asm))
apply (simp (no_asm_simp))
apply (rule_tac x="prx@[node]" in exI)
apply (rule_tac x="sfx" in exI)
apply (rule conjI)
apply assumption
apply (rule conjI)
apply (simp (no_asm))
apply (rule conjI)
apply (assumption)
using [[simp_depth_limit = 100]]
proof - (* From invariant to postcondition *)
fix var low high rep nodeslist ns repa "next" no
assume ns: "List nodeslist next ns"
assume no_in_ns: "no \<in> set ns"
assume while_inv: "\<forall>no\<in>set ns.
repa no \<noteq> Null \<and>
(if (repa \<propto> low) no = (repa \<propto> high) no \<and> high no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set ns.
((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) =
(repa no = repa no1)))"
assume pre: "\<forall>no\<in>set ns.
no \<noteq> Null \<and>
(low no = Null) = (high no = Null) \<and>
low no \<notin> set ns \<and>
high no \<notin> set ns \<and>
isLeaf_pt no low high = (var no \<le> Suc 0) \<and>
(low no \<noteq> Null \<longrightarrow> rep (low no) \<noteq> Null) \<and> (rep \<propto> low) no \<notin> set ns"
assume same_var: "\<forall>no1\<in>set ns. \<forall>no2\<in>set ns. var no1 = var no2"
assume share_case: "(repa \<propto> low) no = (repa \<propto> high) no \<longrightarrow> high no = Null"
assume unmodif: "\<forall>no. no \<notin> set ns \<longrightarrow> rep no = repa no"
show "hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa] \<in> set ns \<and>
repa (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) =
hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]"
proof -
from no_in_ns pre obtain
no_nNull: " no \<noteq> Null" and
no_balanced: "(low no = Null) = (high no = Null)" and
isLeaf_var: "isLeaf_pt no low high = (var no \<le> Suc 0)"
by blast
have repNodes_eq_same_node: "repNodes_eq no no low high repa"
by (simp add: repNodes_eq_def)
from no_in_ns have ns_nempty: "ns \<noteq> []"
by auto
from no_in_ns repNodes_eq_same_node
have repNodes_not_empty: "[sn\<leftarrow>ns . repNodes_eq sn no low high repa] \<noteq> []"
by (rule filter_not_empty)
then have hd_term_in_ns: "hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa] \<in> set ns"
by (rule hd_filter_in_list)
with while_inv obtain
repa_hd_nNull: "repa (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) \<noteq> Null"
by auto
let ?hd = "hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]"
from hd_term_in_ns pre obtain
hd_nNull: " ?hd \<noteq> Null" and
hd_balanced:
"(low (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) = Null) =
(high (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) = Null)" and
hd_isLeaf_var:
"isLeaf_pt (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) low high =
(var (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) \<le> Suc 0)"
by blast
have "repa (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) =
hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]"
proof (cases "high no = Null")
case True
with no_balanced have "low no = Null"
by simp
with True have no_Leaf: "isLeaf_pt no low high"
by (simp add: isLeaf_pt_def)
with isLeaf_var have varno: "var no <= 1"
by simp
from same_var [rule_format, OF no_in_ns hd_term_in_ns] varno
have "var (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) \<le> 1"
by simp
with hd_isLeaf_var have
"isLeaf_pt (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) low high"
by simp
with while_inv hd_term_in_ns repNodes_not_empty show ?thesis
apply (simp add: isLeaf_pt_def)
apply (erule_tac x=
"hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]" in ballE)
prefer 2
apply simp
apply (simp (no_asm_use) add: repNodes_eq_def)
apply (rule filter_hd_P_rep_indep)
apply (simp (no_asm_simp))
apply (simp (no_asm_simp))
apply assumption
done
next
assume hno_nNull: "high no \<noteq> Null"
with share_case have repchildren_neq: "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
by simp
from repNodes_not_empty have
"repNodes_eq (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) no low high repa"
by (rule hd_filter_prop)
then
have "(repa \<propto> low) (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) =
(repa \<propto> low) no \<and>
(repa \<propto> high) (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]) =
(repa \<propto> high) no"
by (simp add: repNodes_eq_def)
with repchildren_neq have
"(repa \<propto> low) (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa])
\<noteq> (repa \<propto> high) (hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa])"
by simp
with while_inv hd_term_in_ns repNodes_not_empty show ?thesis
apply (simp add: isLeaf_pt_def)
apply (erule_tac x=
"hd [sn\<leftarrow>ns . repNodes_eq sn no low high repa]" in ballE)
prefer 2
apply simp
apply (simp (no_asm_use) add: repNodes_eq_def)
apply (rule filter_hd_P_rep_indep)
apply simp
apply fastforce
apply fastforce
done
qed
with hd_term_in_ns
show ?thesis
by simp
qed
next
(* invariant to invariant, THEN part -- REDUCING*)
fix var low high rep nodeslist repa "next" node prx sfx
assume ns: "List nodeslist next (prx @ node # sfx)"
assume sfx: "List (next node) next sfx"
assume node_not_Null: "node \<noteq> Null"
assume nodes_balanced_ordered: "\<forall>no\<in>set (prx @ node # sfx).
no \<noteq> Null \<and>
(low no = Null) = (high no = Null) \<and>
low no \<notin> set (prx @ node # sfx) \<and>
high no \<notin> set (prx @ node # sfx) \<and>
isLeaf_pt no low high = (var no \<le> (1::nat)) \<and>
(low no \<noteq> Null \<longrightarrow> rep (low no) \<noteq> Null) \<and>
(rep \<propto> low) no \<notin> set (prx @ node # sfx)"
assume all_nodes_same_var: "\<forall>no1\<in>set (prx @ node # sfx).
\<forall>no2\<in>set (prx @ node # sfx). var no1 = var no2"
assume rep_repa_nc: "\<forall>no. no \<notin> set prx \<longrightarrow> rep no = repa no"
assume while_inv: "\<forall>no\<in>set prx.
repa no \<noteq> Null \<and>
(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx.
((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) =
(repa no = repa no1)))"
assume not_Leaf: "\<not> isLeaf_pt node low high"
assume repchildren_eq_nln: "repa (low node) = repa (high node)"
show "(\<forall>no. no \<notin> set (prx @ [node]) \<longrightarrow>
rep no = (repa(node := repa (high node))) no) \<and>
(\<forall>no\<in>set (prx @ [node]).
(repa(node := repa (high node))) no \<noteq> Null \<and>
(if (repa(node := repa (high node)) \<propto> low) no =
(repa(node := repa (high node)) \<propto> high) no \<and>
low no \<noteq> Null
then (repa(node := repa (high node))) no =
(repa(node := repa (high node)) \<propto> low) no
else (repa(node := repa (high node))) no =
hd [sn\<leftarrow>prx @ [node] .
repNodes_eq sn no low high
(repa(node := repa (high node)))] \<and>
(repa(node := repa (high node)))
((repa(node := repa (high node))) no) =
(repa(node := repa (high node))) no \<and>
(\<forall>no1\<in>set (prx @ [node]).
((repa(node := repa (high node)) \<propto> high) no1 =
(repa(node := repa (high node)) \<propto> high) no \<and>
(repa(node := repa (high node)) \<propto> low) no1 =
(repa(node := repa (high node)) \<propto> low) no) =
((repa(node := repa (high node))) no =
(repa(node := repa (high node))) no1))))"
(is "?NodesUnmodif \<and> ?NodesModif")
proof -
\<comment> \<open>This proof was originally conducted without the
substitution @{term "repa (low node) = repa (high node)"} preformed.
So don't be confused if we show everythin for @{text "repa (low node)"}.\<close>
from rep_repa_nc
have nodes_unmodif: ?NodesUnmodif
by auto
hence rep_Sucna_nc:
"(\<forall>no. no \<notin> set (prx @ [node])
\<longrightarrow> rep no = (repa(node := repa (low (node )))) no)"
by auto
have nodes_modif: ?NodesModif (is "\<forall>no\<in>set (prx @ [node]). ?P no \<and> ?Q no")
proof (rule ballI)
fix no
assume no_in_take_Sucna: " no \<in> set (prx @ [node])"
show "?P no \<and> ?Q no"
proof (cases "no = node")
case False
note no_noteq_nln=this
with no_in_take_Sucna
have no_in_take_n: "no \<in> set prx"
by auto
with no_in_take_n while_inv obtain
repa_no_nNull: " repa no \<noteq> Null" and
repa_cases: "(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa]
\<and> repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no)
= (repa no = repa no1)))"
using [[simp_depth_limit = 2]]
by auto
from no_in_take_n
have no_in_nodeslist: "no \<in> set (prx @ node # sfx)"
by auto
from repa_no_nNull no_noteq_nln have ext_repa_nNull: "?P no"
by auto
from no_in_nodeslist nodes_balanced_ordered obtain
nln_nNull: "node \<noteq> Null" and
nln_balanced_children: "(low node = Null) = (high node = Null)" and
lnln_notin_nodeslist: "low node \<notin> set (prx @ node # sfx)" and
hnln_notin_nodeslist: "high node \<notin> set (prx @ node # sfx)" and
isLeaf_var_nln: "isLeaf_pt node low high = (var node \<le> 1)" and
node_nNull_rap_nNull_nln: "(low node \<noteq> Null
\<longrightarrow> rep (low node) \<noteq> Null)" and
nln_varrep_le_var: "(rep \<propto> low) node \<notin> set (prx @ node # sfx)"
apply (erule_tac x="node" in ballE)
apply auto
done
from no_in_nodeslist nodes_balanced_ordered no_in_take_Sucna
obtain
no_nNull: "no \<noteq> Null" and
balanced_children: "(low no = Null) = (high no = Null)" and
lno_notin_nodeslist: "low no \<notin> set (prx @ node # sfx)" and
hno_notin_nodeslist: "high no \<notin> set (prx @ node # sfx)" and
isLeaf_var_no: "isLeaf_pt no low high = (var no \<le> 1)" and
node_nNull_rep_nNull: "(low no \<noteq> Null \<longrightarrow> rep (low no) \<noteq> Null)" and
varrep_le_var: "(rep \<propto> low) no \<notin> set (prx @ node # sfx)"
apply -
apply (erule_tac x=no in ballE)
apply auto
done
from lno_notin_nodeslist
have ext_rep_null_comp_low:
"(repa (node := repa (low node)) \<propto> low) no = (repa \<propto> low) no"
by (auto simp add: null_comp_def)
from hno_notin_nodeslist
have ext_rep_null_comp_high:
"(repa (node := repa (low node)) \<propto> high) no = (repa \<propto> high) no"
by (auto simp add: null_comp_def)
have share_reduce_if: "?Q no"
proof (cases "(repa (node := repa (low node)) \<propto> low) no =
(repa(node := repa (low node)) \<propto> high) no \<and> low no \<noteq> Null")
case True
then obtain
red_case: "(repa (node := repa (low node)) \<propto> low) no =
(repa(node := repa (low node)) \<propto> high) no" and
lno_nNull: "low no \<noteq> Null"
by simp
from lno_nNull balanced_children have hno_nNull: "high no \<noteq> Null"
by simp
from True ext_rep_null_comp_low ext_rep_null_comp_high
have repchildren_eq_no: "(repa \<propto> low) no = (repa \<propto> high) no"
by simp
with repa_cases lno_nNull have "repa no = (repa \<propto> low) no"
by auto
with ext_rep_null_comp_low no_noteq_nln
have "(repa(node := repa (low node))) no =
(repa (node := repa (low node)) \<propto> low) no"
by simp
with True repchildren_eq_nln show ?thesis
by auto
next
assume share_case_ext:
" \<not> ((repa(node := repa (low node)) \<propto> low) no =
(repa(node := repa (low node)) \<propto> high) no \<and> low no \<noteq> Null)"
from not_Leaf isLeaf_var_nln
have "1 < var node"
by simp
with all_nodes_same_var
have all_nodes_nl_Suc0_l_var: "\<forall>x \<in> set (prx @ node # sfx). 1 < var x"
using [[simp_depth_limit=1]]
by auto
with nodes_balanced_ordered
have all_nodes_nl_noLeaf:
"\<forall>x \<in> set (prx @ node # sfx). \<not> isLeaf_pt x low high"
apply -
apply rule
apply (drule_tac x=x in bspec,assumption)
apply (drule_tac x=x in bspec,assumption)
apply auto
done
from nodes_balanced_ordered
have all_nodes_nl_balanced:
"\<forall>x \<in> set (prx @ node # sfx). (low x = Null) = (high x = Null)"
apply -
apply rule
apply (drule_tac x=x in bspec,assumption)
apply auto
done
from all_nodes_nl_Suc0_l_var no_in_nodeslist
have Suc0_l_var_no: "1 < var no"
by auto
with isLeaf_var_no have no_nLeaf: " \<not> isLeaf_pt no low high"
by simp
with balanced_children have lno_nNull: "low no \<noteq> Null"
by (simp add: isLeaf_pt_def)
with balanced_children have hno_nNull: "high no \<noteq> Null"
by simp
with share_case_ext ext_rep_null_comp_low ext_rep_null_comp_high lno_nNull
have repchildren_neq_no: "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
by (simp add: null_comp_def)
with repa_cases
have share_case_inv:
"repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1))"
by auto
then have repa_no: "repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa]"
by simp
from Suc0_l_var_no have "\<forall>x \<in> set (prx @ node # sfx). 1 < var no"
by auto
from no_in_take_n have "[sn\<leftarrow>prx . repNodes_eq sn no low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have "repNodes_eq
(hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa]) no low high repa"
by (rule hd_filter_prop)
with repa_no
have rep_children_eq_no_repa_no:
"(repa \<propto> low) (repa no) = (repa \<propto> low) no \<and>
(repa \<propto> high) (repa no) = (repa \<propto> high) no"
by (simp add: repNodes_eq_def)
from lno_notin_nodeslist rep_repa_nc
have rep_repa_nc_low_no: "rep (low no) = repa (low no)"
apply -
apply (erule_tac x="low no" in allE)
apply auto
done
have "\<forall>x \<in> set (prx @ [node]).
repNodes_eq x no low high (repa(node := repa (low node))) =
repNodes_eq x no low high repa"
proof (rule ballI, unfold repNodes_eq_def)
fix x
assume x_in_take_Sucn: " x \<in> set (prx @ [node])"
hence x_in_nodeslist: "x \<in> set (prx @ node # sfx)"
by auto
with all_nodes_nl_noLeaf nodes_balanced_ordered
have children_nNull_x: "low x \<noteq> Null \<and> high x \<noteq> Null"
apply -
apply (drule_tac x=x in bspec,assumption)
apply (drule_tac x=x in bspec,assumption)
apply (auto simp add: isLeaf_pt_def)
done
from x_in_nodeslist nodes_balanced_ordered
have "low x \<notin> set (prx @ node # sfx) \<and> high x \<notin> set (prx @ node # sfx)"
apply -
apply (drule_tac x=x in bspec,assumption)
apply auto
done
with lno_notin_nodeslist hno_notin_nodeslist
children_nNull_x lno_nNull hno_nNull
show "((repa(node := repa (low node)) \<propto> high) x =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) x =
(repa(node := repa (low node)) \<propto> low) no) =
((repa \<propto> high) x = (repa \<propto> high) no \<and>
(repa \<propto> low) x = (repa \<propto> low) no)"
by (simp add: null_comp_def)
qed
then have filter_extrep_rep:
"[sn\<leftarrow>(prx @ [node]). repNodes_eq sn no low high
(repa(node := repa (low node)))] =
[sn\<leftarrow>(prx @ [node]) . repNodes_eq sn no low high repa]"
by (rule P_eq_list_filter)
from no_in_take_n
have filter_n_notempty: "[sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<noteq> []"
apply (rule filter_not_empty)
apply (simp add: repNodes_eq_def)
done
then have "hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] =
hd [sn\<leftarrow>prx@[node]. repNodes_eq sn no low high repa]"
by auto
with no_noteq_nln filter_extrep_rep repa_no
have ext_repa_no: "(repa(node:= repa (low node))) no =
hd [sn\<leftarrow>prx@[node] . repNodes_eq sn no low high
(repa(node := repa (low node)))]"
by simp
have "(repa(node := repa (low node))) (repa no) = repa no"
proof (cases "repa no = node")
case True
note rno_nln=this
from rep_repa_nc_low_no rep_children_eq_no_repa_no lno_nNull
node_nNull_rep_nNull
have low_rep_no_nNull: "low (repa no) \<noteq> Null"
apply (simp add: null_comp_def)
apply auto
done
with nodes_balanced_ordered rno_nln
have high_rap_no_nNull: "high (repa no) \<noteq> Null"
apply -
apply (drule_tac x="repa no" in bspec)
apply auto
done
with low_rep_no_nNull rno_nln rep_children_eq_no_repa_no
have "repa (low node) = (repa \<propto> low) no \<and>
repa (high node) = (repa \<propto> high) no"
by (simp add: null_comp_def)
with repchildren_eq_nln have " (repa \<propto> low) no = (repa \<propto> high) no"
by simp
with repchildren_neq_no show ?thesis
by simp
next
assume rno_not_nln: "repa no \<noteq> node"
from share_case_inv have "repa (repa no) = repa no"
by auto
with rno_not_nln show ?thesis
by simp
qed
with no_noteq_nln have ext_repa_ext_repa:
"(repa(node := repa (low node)))
((repa(node := repa (low node))) no)
= (repa(node := repa (low node))) no"
by simp
have "(\<forall>no1\<in>set (prx@[node]).
((repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no) =
((repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1))"
proof (rule ballI)
fix no1
assume no1_in_take_Sucn: " no1 \<in> set (prx@[node])"
hence no1_in_nodeslist: "no1 \<in> set (prx @ node # sfx)"
by auto
show "((repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no) =
((repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1)"
proof (cases "no1 = node")
case True
show ?thesis
proof (rule, elim conjE)
assume ext_repa_no_no1:
"(repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1"
with True no_noteq_nln
have repa_no_repa_low_nln: "repa no = repa (low node)"
by simp
from filter_n_notempty
have repa_no_in_take_n:
"hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa]
\<in> set prx "
apply -
apply (rule hd_filter_in_list)
apply auto
done
with repa_no
have repa_no_in_nodeslist: "repa no \<in> set (prx @ node # sfx)"
by auto
from lnln_notin_nodeslist rep_repa_nc
have rep_repa_low_nln: "rep (low node) = repa (low node)"
by auto
from all_nodes_nl_noLeaf nln_balanced_children
have "low node \<noteq> Null"
by (auto simp add: isLeaf_pt_def)
with rep_repa_low_nln lnln_notin_nodeslist lno_nNull
nln_varrep_le_var
have "repa (low node) \<notin> set (prx @ node # sfx)"
by (simp add: null_comp_def)
with repa_no_repa_low_nln repa_no_in_nodeslist
show "(repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no"
by simp
next
assume no_no1_high:
"(repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no"
assume no_no1_low:
"(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no"
from True repchildren_eq_nln
have repachildren_eq_no1: " repa (low no1) = repa (high no1)"
by simp
from not_Leaf True nln_balanced_children
have children_nNull_no1: "(low no1) \<noteq> Null \<and> high no1 \<noteq> Null"
by (simp add: isLeaf_pt_def)
with repachildren_eq_no1
have repchildren_eq_no1: "(repa \<propto> low) no1 = (repa \<propto> high) no1"
by (simp add: null_comp_def)
from no_no1_low children_nNull_no1 lno_nNull
lnln_notin_nodeslist lno_notin_nodeslist True
have rep_low_eq_no_no1: "(repa \<propto> low) no1 = (repa \<propto> low) no"
by (simp add: null_comp_def)
from no_no1_high children_nNull_no1 hno_nNull
hnln_notin_nodeslist hno_notin_nodeslist True
have rep_high_eq_no_no1: "(repa \<propto> high) no1 = (repa \<propto> high) no"
by (simp add: null_comp_def)
with rep_low_eq_no_no1 repchildren_eq_no1
have "(repa \<propto> low) no = (repa \<propto> high) no"
by simp
with repchildren_neq_no
show "(repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1"
by simp
qed
next
assume no1_neq_nln: "no1 \<noteq> node"
from no1_in_nodeslist nodes_balanced_ordered
have children_notin_nl_no1:
"low no1 \<notin> set (prx @ node # sfx) \<and> high no1 \<notin> set (prx @ node # sfx)"
apply -
apply (drule_tac x=no1 in bspec,assumption)
by auto
from no1_neq_nln no1_in_take_Sucn
have no1_in_take_n: "no1 \<in> set prx"
by auto
from no1_in_nodeslist all_nodes_nl_noLeaf all_nodes_nl_balanced
have children_nNull_no1: "(low no1) \<noteq> Null \<and> high no1 \<noteq> Null"
by (auto simp add: isLeaf_pt_def)
show ?thesis
proof (rule, elim conjE)
assume ext_repa_high_no1_no:
"(repa(node := repa (low node)) \<propto> high) no1
= (repa(node := repa (low node)) \<propto> high) no"
assume ext_repa_low_no1_no:
"(repa(node := repa (low node)) \<propto> low) no1
= (repa(node := repa (low node)) \<propto> low) no"
from children_nNull_no1 hno_nNull ext_repa_high_no1_no
children_notin_nl_no1
hno_notin_nodeslist
have repa_high_no1_no: "(repa \<propto> high) no1 = (repa \<propto> high) no"
by (simp add: null_comp_def)
from children_nNull_no1 lno_nNull ext_repa_low_no1_no
children_notin_nl_no1 lno_notin_nodeslist
have repa_low_no1_no: "(repa \<propto> low) no1 = (repa \<propto> low) no"
by (simp add: null_comp_def)
from repchildren_neq_no repa_high_no1_no repa_low_no1_no
have "(repa \<propto> low) no1 \<noteq> (repa \<propto> high) no1"
by simp
from no1_in_take_n share_case_inv repa_high_no1_no repa_low_no1_no
have "repa no = repa no1"
by auto
with no_noteq_nln no1_neq_nln
show " (repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1"
by simp
next
assume "(repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1"
with no_noteq_nln no1_neq_nln
have "repa no = repa no1"
by simp
with share_case_inv no1_in_take_n
have "((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no)"
by auto
with children_notin_nl_no1 children_nNull_no1 lno_notin_nodeslist
hno_notin_nodeslist lno_nNull hno_nNull
show "(repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no"
by (auto simp add: null_comp_def)
qed
qed
qed
from ext_repa_ext_repa ext_repa_no share_case_ext repchildren_eq_nln this
show ?thesis
using [[simp_depth_limit=4]]
by auto
qed
with ext_repa_nNull show ?thesis
by auto
next
assume no_nln: "no = node"
hence no_in_nodeslist: "no \<in> set (prx @ node # sfx)"
by simp
from no_nln not_Leaf no_in_nodeslist
nodes_balanced_ordered [rule_format, OF this] obtain
low_no_nNull: "low no \<noteq> Null" and
high_no_nNull: "high no \<noteq> Null" and
rep_low_no_nNull: "rep (low no) \<noteq> Null" and
lno_notin_nl: "low no \<notin> set (prx @ node # sfx)" and
hno_notin_nl: "high no \<notin> set (prx @ node # sfx)" and
children_nNull_no: "(low no \<noteq> Null) \<and> (high no \<noteq> Null)"
apply (unfold isLeaf_pt_def)
apply blast
done
then have "low no \<notin> set prx"
by auto
with rep_repa_nc no_nln rep_low_no_nNull
have "(repa(node := repa (low node))) no \<noteq> Null"
by simp
moreover
have "(if (repa(node := repa (low node)) \<propto> low) no =
(repa(node := repa (low node)) \<propto> high) no \<and> low no \<noteq> Null
then (repa(node := repa (low node))) no =
(repa(node := repa (low node)) \<propto> low) no
else (repa(node := repa (low node))) no =
hd [sn\<leftarrow>prx@[node]. repNodes_eq sn no low high
(repa(node := repa (low node)))] \<and>
(repa(node := repa (low node)))
((repa(node := repa (low node))) no) =
(repa(node := repa (low node))) no \<and>
(\<forall>no1\<in>set (prx@[node]).
((repa(node := repa (low node)) \<propto> high) no1 =
(repa(node := repa (low node)) \<propto> high) no \<and>
(repa(node := repa (low node)) \<propto> low) no1 =
(repa(node := repa (low node)) \<propto> low) no) =
((repa(node := repa (low node))) no =
(repa(node := repa (low node))) no1)))"
proof (cases "(repa(node := repa (low node)) \<propto> low) no =
(repa(node := repa (low node)) \<propto> high) no \<and> low no \<noteq> Null")
case True
note red_case=this
with children_nNull_no lno_notin_nl hno_notin_nl
have "(repa \<propto> low) no = (repa \<propto> high) no"
by (auto simp add: null_comp_def)
from children_nNull_no lno_notin_nl
have ext_repa_eq_repa_low: "(repa(node := repa (low node)) \<propto> low) no
= (repa \<propto> low) no "
by (auto simp add: null_comp_def)
from children_nNull_no hno_notin_nl
have ext_repa_eq_repa_high:
"(repa(node := repa (low node)) \<propto> high) no
= (repa \<propto> high) no "
by (auto simp add: null_comp_def)
from no_nln children_nNull_no
have "repa (low node) = (repa \<propto> low) no"
by (simp add: null_comp_def)
with red_case ext_repa_eq_repa_high ext_repa_eq_repa_low no_nln
show ?thesis
using [[simp_depth_limit=2]]
by (auto simp del: null_comp_not_Null)
next
assume share_case: " \<not> ((repa(node := repa (low node)) \<propto> low) no
= (repa(node := repa (low node)) \<propto> high) no \<and> low no \<noteq> Null)"
with low_no_nNull have "(repa(node := repa (low node)) \<propto> low) no
\<noteq> (repa(node := repa (low node)) \<propto> high) no"
by simp
with children_nNull_no lno_notin_nl hno_notin_nl
have "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
by (auto simp add: null_comp_def)
with children_nNull_no have "repa (low no) \<noteq> repa (high no)"
by (simp add: null_comp_def)
with repchildren_eq_nln no_nln show ?thesis
by simp
qed
ultimately show ?thesis
using repchildren_eq_nln
apply -
apply (simp only:)
apply (simp (no_asm))
done
qed
qed
from nodes_unmodif nodes_modif
show ?thesis by iprover
qed
next
fix var low high rep nodeslist repa "next" node prx sfx repb
assume ns: "List nodeslist next (prx @ node # sfx)"
assume sfx: "List (next node) next sfx"
assume nodes_balanced_ordered: "\<forall>no\<in>set (prx @ node # sfx).
no \<noteq> Null \<and>
(low no = Null) = (high no = Null) \<and>
low no \<notin> set (prx @ node # sfx) \<and>
high no \<notin> set (prx @ node # sfx) \<and>
isLeaf_pt no low high = (var no \<le> (1::nat)) \<and>
(low no \<noteq> Null \<longrightarrow> rep (low no) \<noteq> Null) \<and>
(rep \<propto> low) no \<notin> set (prx @ node # sfx)"
assume all_nodes_same_var: "\<forall>no1\<in>set (prx @ node # sfx).
\<forall>no2\<in>set (prx @ node # sfx). var no1 = var no2"
assume rep_repa_nc: "\<forall>no. no \<notin> set prx \<longrightarrow> rep no = repa no"
assume while_inv: "\<forall>no\<in>set prx.
repa no \<noteq> Null \<and>
(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx.
((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) =
(repa no = repa no1)))"
assume share_cond:
"\<not> (\<not> isLeaf_pt node low high \<and> repa (low node) = repa (high node))"
assume repb_node:
"repb node = hd [sn\<leftarrow>prx @ node # sfx . repNodes_eq sn node low high repa]"
assume repa_repb_nc: "\<forall>pt. pt \<noteq> node \<longrightarrow> repa pt = repb pt"
assume var_repb_node: "var (repb node) = var node"
show "(\<forall>no. no \<notin> set (prx @ [node]) \<longrightarrow> rep no = repb no) \<and>
(\<forall>no\<in>set (prx @ [node]).
repb no \<noteq> Null \<and>
(if (repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null
then repb no = (repb \<propto> low) no
else repb no =
hd [sn\<leftarrow>prx @ [node] . repNodes_eq sn no low high repb] \<and>
repb (repb no) = repb no \<and>
(\<forall>no1\<in>set (prx @ [node]).
((repb \<propto> high) no1 = (repb \<propto> high) no \<and>
(repb \<propto> low) no1 = (repb \<propto> low) no) =
(repb no = repb no1))))"
proof -
have rep_repb_nc: "(\<forall>no. no \<notin> set (prx @ [node]) \<longrightarrow> rep no = repb no)"
proof (intro allI impI)
fix no
assume no_notin_take_Sucn: "no \<notin> set (prx @ [node])"
with rep_repa_nc
have rep_repa_nc_Sucn: "rep no = repa no"
by auto
from no_notin_take_Sucn have "no \<noteq> node"
by auto
with repa_repb_nc have "repa no = repb no"
by auto
with rep_repa_nc_Sucn show "rep no = repb no"
by simp
qed
moreover
have repb_no_share_def:
"(\<forall>no\<in>set (prx @ [node]).
\<not> ((repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null) \<longrightarrow>
repb no = hd [sn\<leftarrow>(prx @ [node]) . repNodes_eq sn no low high repb])"
proof (intro ballI impI)
fix no
assume no_in_take_Sucn: " no \<in> set (prx @ [node])"
assume share_prop: "\<not> ((repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null)"
from share_prop have share_or:
"(repb \<propto> low) no \<noteq> (repb \<propto> high) no \<or> low no = Null"
using [[simp_depth_limit=2]]
by simp
from no_in_take_Sucn have no_in_nl: "no \<in> set (prx @ node # sfx)"
by auto
from nodes_balanced_ordered [rule_format, OF this] obtain
no_nNull: "no \<noteq> Null" and
balanced_no: "(low no = Null) = (high no = Null)" and
lno_notin_nl: "low no \<notin> set (prx @ node # sfx)" and
hno_notin_nl: "high no \<notin> set (prx @ node # sfx)" and
isLeaf_var_no: "isLeaf_pt no low high = (var no \<le> 1)"
by auto
have nodes_notin_nl_neq_nln: "\<forall>p. p \<notin> set (prx @ node # sfx) \<longrightarrow> p \<noteq> node "
by auto
show " repb no = hd [sn\<leftarrow>(prx @ [node]). repNodes_eq sn no low high repb]"
proof (cases "no = node")
case False
note no_notin_nl=this
with no_in_take_Sucn have no_in_take_n: "no \<in> set prx"
by auto
from False repa_repb_nc have repb_repa_no: "repb no = repa no"
by auto
with while_inv [rule_format, OF no_in_take_n] no_in_take_n obtain
repa_no_nNull: "repa no \<noteq> Null" and
while_share_red_exp:
"(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1)))"
using [[simp_depth_limit = 2]]
by auto
from no_in_take_n
have filter_take_n_notempty: "[sn\<leftarrow>prx.
repNodes_eq sn no low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have hd_term_n_Sucn:
"hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa]
= hd [sn\<leftarrow>prx@[node] . repNodes_eq sn no low high repa]"
by auto
thus ?thesis
proof (cases "low no = Null")
case True
note lno_Null=this
with balanced_no have hno_Null: "high no = Null"
by simp
from lno_Null hno_Null have isLeaf_no: "isLeaf_pt no low high"
by (simp add: isLeaf_pt_def)
from True while_share_red_exp
have while_low_Null:
"repa no = hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1))"
by auto
have all_nodes_in_nl_Leafs:
"\<forall>x \<in> set (prx @ node # sfx). isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nodeslist: "x \<in> set (prx @ node # sfx)"
from isLeaf_no isLeaf_var_no have "var no \<le> 1"
by simp
with all_nodes_same_var [rule_format, OF x_in_nodeslist no_in_nl]
have "var x \<le> 1"
by simp
with nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
show "isLeaf_pt x low high"
by (auto simp add: isLeaf_pt_def)
qed
have "\<forall> x \<in> set (prx@[node]). repNodes_eq x no low high repb
= repNodes_eq x no low high repa"
proof (rule ballI)
fix x
assume x_in_take_Sucn: "x \<in> set (prx@[node])"
hence x_in_nodeslist: "x \<in> set (prx @ node # sfx)"
by auto
with all_nodes_in_nl_Leafs have "isLeaf_pt x low high"
by auto
with isLeaf_no repa_repb_nc show "repNodes_eq x no low high repb
= repNodes_eq x no low high repa"
by (simp add: repNodes_eq_def null_comp_def isLeaf_pt_def)
qed
then have " [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repa]
= [sn\<leftarrow>(prx@[node]) . repNodes_eq sn no low high repb]"
apply -
apply (rule P_eq_list_filter)
apply simp
done
with hd_term_n_Sucn while_low_Null repb_repa_no show ?thesis
by auto
next
assume lno_nNull: " low no \<noteq> Null"
with balanced_no have hno_nNull: "high no \<noteq> Null"
by simp
with lno_nNull have no_nLeaf: "\<not> isLeaf_pt no low high"
by (simp add: isLeaf_pt_def)
with isLeaf_var_no have Sucn_s_varno: "1 < var no"
by auto
with no_in_nl all_nodes_same_var
have all_nodes_nl_var: "\<forall> x \<in> set (prx @ node # sfx). 1 < var x"
apply -
apply (rule ballI)
apply (drule_tac x=no in bspec,assumption)
apply (drule_tac x=x in bspec,assumption)
apply auto
done
with nodes_balanced_ordered
have all_nodes_nl_nLeaf:
"\<forall>x \<in> set (prx @ node # sfx). \<not> isLeaf_pt x low high"
apply -
apply (rule ballI)
apply (drule_tac x=x in bspec,assumption)
apply (drule_tac x=x in bspec,assumption)
apply auto
done
from lno_nNull share_or
have repbchildren_eq_no: "(repb \<propto> low) no \<noteq> (repb \<propto> high) no"
by simp
with lno_nNull hno_nNull lno_notin_nl hno_notin_nl repa_repb_nc
nodes_notin_nl_neq_nln
have repachildren_eq_no: "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
using [[simp_depth_limit=2]]
by (simp add: null_comp_def)
with while_share_red_exp
have repa_no_def:
"repa no = hd [sn\<leftarrow>prx . repNodes_eq sn no low high repa] "
by auto
with no_notin_nl repa_repb_nc
have "repb no = hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] "
by simp
with hd_term_n_Sucn
have repb_no_hd_term_repa: "repb no =
hd [sn\<leftarrow>prx@[node] . repNodes_eq sn no low high repa] "
by simp
have "\<forall>x \<in> set (prx@[node]).
repNodes_eq x no low high repa = repNodes_eq x no low high repb"
proof (intro ballI)
fix x
assume x_in_take_Sucn: "x \<in> set (prx@[node]) "
hence x_in_nodeslist: "x \<in> set (prx @ node # sfx)"
by auto
with all_nodes_nl_nLeaf have x_nLeaf: "\<not> isLeaf_pt x low high"
by auto
from nodes_balanced_ordered [rule_format, OF x_in_nodeslist] obtain
balanced_x: "(low x = Null) = (high x = Null)" and
lx_notin_nl: "low x \<notin> set (prx @ node # sfx)" and
hx_notin_nl: "high x \<notin> set (prx @ node # sfx)"
by auto
with nodes_notin_nl_neq_nln lno_notin_nl hno_notin_nl lno_nNull
hno_nNull repa_repb_nc
show " repNodes_eq x no low high repa = repNodes_eq x no low high repb"
by (simp add: repNodes_eq_def null_comp_def)
qed
then have " [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repa] =
[sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
apply -
apply (rule P_eq_list_filter)
apply auto
done
with repb_no_hd_term_repa show ?thesis
by simp
qed
next
assume no_nln: "no = node"
with repb_node have repb_no_def: "repb no =
hd [sn\<leftarrow>(prx @ node # sfx). repNodes_eq sn node low high repa]"
by simp
show ?thesis
proof (cases "isLeaf_pt no low high")
case True
note isLeaf_no=this
have "\<forall>x \<in> set (prx @ node # sfx). repNodes_eq x no low high repb
= repNodes_eq x no low high repa"
proof (rule ballI)
fix x
assume x_in_nodeslist: "x \<in> set (prx @ node # sfx)"
have all_nodes_in_nl_Leafs:
"\<forall>x \<in> set (prx @ node # sfx). isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nodeslist: " x \<in> set (prx @ node # sfx)"
from isLeaf_no isLeaf_var_no have "var no \<le> 1"
by simp
with all_nodes_same_var [rule_format, OF x_in_nodeslist no_in_nl]
have "var x \<le> 1"
by simp
with nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
show "isLeaf_pt x low high"
by (auto simp add: isLeaf_pt_def)
qed
with x_in_nodeslist have "isLeaf_pt x low high"
by auto
with isLeaf_no repa_repb_nc
show "repNodes_eq x no low high repb = repNodes_eq x no low high repa"
by (simp add: repNodes_eq_def null_comp_def isLeaf_pt_def)
qed
with repb_no_def no_nln have repb_no_whole_nl: "repb no =
hd [sn\<leftarrow> (prx @ node # sfx). repNodes_eq sn node low high repb]"
apply -
apply (subgoal_tac
"[sn\<leftarrow> (prx@node#sfx). repNodes_eq sn node low high repa]
= [sn\<leftarrow>(prx @ node # sfx) . repNodes_eq sn node low high repb]")
apply simp
apply (rule P_eq_list_filter)
apply auto
done
from no_in_take_Sucn no_nln
have "[sn\<leftarrow> (prx@[node]). repNodes_eq sn node low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then
have "hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn node low high repb] =
hd [sn\<leftarrow>(prx @ node # sfx). repNodes_eq sn node low high repb]"
apply -
apply (rule hd_filter_app [symmetric])
apply auto
done
with repb_no_whole_nl no_nln show ?thesis
by simp
next
assume no_nLeaf: " \<not> isLeaf_pt no low high"
with share_or balanced_no have "(repb \<propto> low) no \<noteq> (repb \<propto> high) no"
using [[simp_depth_limit=2]]
by (simp add: isLeaf_pt_def)
from no_nLeaf share_cond no_nln have "repa (low no) \<noteq> repa (high no)"
by auto
with no_nLeaf balanced_no have "(repa \<propto> low) no \<noteq> (repa \<propto> high) no "
by (simp add: null_comp_def isLeaf_pt_def)
have "\<forall> x \<in> set (prx@node#sfx). repNodes_eq x no low high repb
= repNodes_eq x no low high repa"
proof (rule ballI)
fix x
assume x_in_nodeslist: " x \<in> set (prx@node#sfx)"
have all_nodes_in_nl_Leafs:
"\<forall>x \<in> set (prx@node#sfx). \<not> isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nodeslist: " x \<in> set (prx@node#sfx)"
from no_nLeaf isLeaf_var_no have "1 < var no "
by simp
with all_nodes_same_var [rule_format, OF x_in_nodeslist no_in_nl]
have "1 < var x"
by auto
with nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
show "\<not> isLeaf_pt x low high"
apply (unfold isLeaf_pt_def)
apply fastforce
done
qed
with x_in_nodeslist have x_nLeaf: "\<not> isLeaf_pt x low high"
by auto
from nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
have "(low x = Null) = (high x = Null)
\<and> low x \<notin> set (prx@node#sfx) \<and> high x \<notin> set (prx@node#sfx)"
by auto
with x_nLeaf balanced_no no_nLeaf repa_repb_nc
nodes_notin_nl_neq_nln lno_notin_nl hno_notin_nl
show "repNodes_eq x no low high repb = repNodes_eq x no low high repa"
using [[simp_depth_limit=2]]
by (simp add: repNodes_eq_def null_comp_def isLeaf_pt_def)
qed
with repb_no_def no_nln
have repb_no_whole_nl:
"repb no = hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn node low high repb]"
apply -
apply (subgoal_tac
"[sn\<leftarrow>(prx@node#sfx). repNodes_eq sn node low high repa]
= [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn node low high repb]")
apply simp
apply (rule P_eq_list_filter)
apply auto
done
from no_in_take_Sucn no_nln
have "[sn\<leftarrow>(prx@[node]) . repNodes_eq sn node low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have
"hd [sn\<leftarrow> (prx@[node]) . repNodes_eq sn node low high repb] =
hd [sn\<leftarrow>(prx@node#sfx) . repNodes_eq sn node low high repb]"
apply -
apply (rule hd_filter_app [symmetric])
apply auto
done
with repb_no_whole_nl no_nln show ?thesis
by simp
qed
qed
qed
have repb_no_red_def: "(\<forall>no\<in>set (prx@[node]).(repb \<propto> low) no = (repb \<propto> high) no
\<and> low no \<noteq> Null \<longrightarrow> repb no = (repb \<propto> low) no)"
proof (intro ballI impI)
fix no
assume no_in_take_Sucn: "no \<in> set (prx@[node])"
assume red_cond_no: " (repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null"
from no_in_take_Sucn have no_in_nl: "no \<in> set (prx@node#sfx)"
by auto
from nodes_balanced_ordered [rule_format, OF this]obtain
no_nNull: "no \<noteq> Null" and
balanced_no: "(low no = Null) = (high no = Null)" and
lno_notin_nl: "low no \<notin> set (prx@node#sfx)" and
hno_notin_nl: "high no \<notin> set (prx@node#sfx)" and
isLeaf_var_no: "isLeaf_pt no low high = (var no \<le> 1)"
by auto
have nodes_notin_nl_neq_nln: "\<forall> p. p \<notin> set (prx@node#sfx) \<longrightarrow> p \<noteq> node"
by auto
show " repb no = (repb \<propto> low) no"
proof (cases "no = node")
case False
note no_notin_nl=this
with no_in_take_Sucn have no_in_take_n: "no \<in> set prx"
by auto
from False repa_repb_nc have repb_repa_no: "repb no = repa no"
by auto
with while_inv [rule_format, OF no_in_take_n] obtain
repa_no_nNull: "repa no \<noteq> Null" and
while_share_red_exp:
"(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1)))"
using [[simp_depth_limit=2]]
by auto
from red_cond_no nodes_notin_nl_neq_nln lno_notin_nl
hno_notin_nl while_share_red_exp balanced_no repa_repb_nc
have red_repa_no: "repa no = (repa \<propto> low) no"
by (auto simp add: null_comp_def)
from red_cond_no nodes_notin_nl_neq_nln lno_notin_nl repa_repb_nc
have "(repb \<propto> low) no = (repa \<propto> low) no"
by (auto simp add: null_comp_def)
with red_repa_no no_notin_nl balanced_no repa_repb_nc
have "repb no = (repb \<propto> low) no"
by auto
with red_cond_no show ?thesis
by auto
next
assume "no = node"
with share_cond
have share_cond_pre:
"isLeaf_pt no low high \<or> repa (low no) \<noteq> repa (high no)"
by simp
show ?thesis
proof (cases "isLeaf_pt no low high")
case True
with red_cond_no show ?thesis
by (simp add: isLeaf_pt_def)
next
assume no_nLeaf: "\<not> isLeaf_pt no low high"
with share_cond_pre
have "repa (low no) \<noteq> repa (high no)"
by simp
with no_nLeaf lno_notin_nl hno_notin_nl nodes_notin_nl_neq_nln
balanced_no repa_repb_nc
have "repb (low no) \<noteq> repb (high no)"
using [[simp_depth_limit=2]]
by (auto simp add: isLeaf_pt_def)
with no_nLeaf balanced_no have "(repb \<propto> low) no \<noteq> (repb \<propto> high) no"
by (simp add: null_comp_def isLeaf_pt_def)
with red_cond_no show ?thesis
by simp
qed
qed
qed
have while_while: "(\<forall>no\<in>set (prx@[node]).
repb no \<noteq> Null \<and>
(if (repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null
then repb no = (repb \<propto> low) no
else repb no = hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb] \<and>
repb (repb no) = repb no \<and>
(\<forall>no1\<in>set ((prx@[node])). ((repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1))))"
(is "\<forall>no\<in>set (prx@[node]). ?P no \<and> ?Q no")
proof (intro ballI)
fix no
assume no_in_take_Sucn: "no \<in> set (prx@[node])"
hence no_in_nl: "no \<in> set (prx@node#sfx)"
by auto
from nodes_balanced_ordered [rule_format, OF this] obtain
no_nNull: "no \<noteq> Null" and
balanced_no: "(low no = Null) = (high no = Null)" and
lno_notin_nl: "low no \<notin> set (prx@node#sfx)" and
hno_notin_nl: "high no \<notin> set (prx@node#sfx)" and
isLeaf_var_no: "isLeaf_pt no low high = (var no \<le> 1)"
by auto
from no_in_take_Sucn
have filter_take_Sucn_not_empty:
"[sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have hd_filter_Sucn_in_Sucn:
"hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb] \<in>
set (prx@[node])"
by (rule hd_filter_in_list)
have nodes_notin_nl_neq_nln: "\<forall>p. p \<notin> set (prx@node#sfx) \<longrightarrow> p \<noteq> node"
by auto
show "?P no \<and> ?Q no"
proof (cases "no = node")
case False
note no_notin_nl=this
with no_in_take_Sucn
have no_in_take_n: "no \<in> set prx"
by auto
from False repa_repb_nc have repb_repa_no: "repb no = repa no"
by auto
with while_inv [rule_format, OF no_in_take_n] obtain
repa_no_nNull: "repa no \<noteq> Null" and
while_share_red_exp:
"(if (repa \<propto> low) no = (repa \<propto> high) no \<and> low no \<noteq> Null
then repa no = (repa \<propto> low) no
else repa no = hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no \<and>
(repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1)))"
using [[simp_depth_limit=2]]
by auto
from repb_repa_no repa_no_nNull have repb_no_nNull: "?P no"
by simp
have "?Q no"
proof (cases "(repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null")
case True
with no_in_take_Sucn repb_no_red_def show ?thesis
by auto
next
assume share_case_repb:
" \<not> ((repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null)"
with repb_no_share_def no_in_take_Sucn
have repb_no_def: "repb no = hd [sn\<leftarrow> (prx@[node]).
repNodes_eq sn no low high repb]"
by auto
with share_case_repb
have "(repb \<propto> low) no \<noteq> (repb \<propto> high) no \<or> low no = Null"
using [[simp_depth_limit=2]]
by simp
thus ?thesis
proof (cases "low no = Null")
case True
note lno_Null=this
with balanced_no have hno_Null: "high no = Null"
by simp
from lno_Null hno_Null have isLeaf_no: "isLeaf_pt no low high"
by (simp add: isLeaf_pt_def)
from True while_share_red_exp
have while_low_Null:
"repa no = hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<and>
repa (repa no) = repa no \<and>
(\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1))"
by auto
from no_in_take_n
have "[sn\<leftarrow>prx. repNodes_eq sn no low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have hd_term_n_Sucn: "hd [sn\<leftarrow>prx. repNodes_eq sn no low high repa] =
hd [sn\<leftarrow>(prx@[node]) . repNodes_eq sn no low high repa]"
apply -
apply (rule hd_filter_app [symmetric])
apply auto
done
have all_nodes_in_nl_Leafs:
"\<forall>x \<in> set (prx@node#sfx). isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nodeslist: " x \<in> set (prx@node#sfx)"
from isLeaf_no isLeaf_var_no have "var no \<le> 1"
by simp
with all_nodes_same_var [rule_format, OF x_in_nodeslist no_in_nl]
have "var x \<le> 1"
by simp
with nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
show "isLeaf_pt x low high"
by (auto simp add: isLeaf_pt_def)
qed
from no_in_take_Sucn have
filter_Sucn_no_notempty:
"[sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have hd_term_in_take_Sucn:
"hd [sn\<leftarrow>(prx@[node]) . repNodes_eq sn no low high repb]
\<in> set (prx@[node])"
by (rule hd_filter_in_list)
then have hd_term_in_nl:
"hd [sn\<leftarrow>(prx@[node]) . repNodes_eq sn no low high repb]
\<in> set (prx@node#sfx)"
by auto
with all_nodes_in_nl_Leafs
have hd_term_Leaf: "isLeaf_pt (hd [sn\<leftarrow> (prx@[node]).
repNodes_eq sn no low high repb]) low high "
by auto
from while_low_Null have "repa (repa no) = repa no"
by auto
with no_notin_nl repa_repb_nc
have repa_repb_no_repb: "repa (repb no) = repb no"
by auto
have repb_repb_no: "repb (repb no) = repb no"
proof (cases "repb no = node")
case False
with repa_repb_nc repa_repb_no_repb show ?thesis
by auto
next
assume repb_no_nln: " repb no = node"
with hd_term_Leaf isLeaf_no all_nodes_in_nl_Leafs
have nested_hd_repa_repb:
"hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
(hd [sn\<leftarrow>(prx@[node]) . repNodes_eq sn no low high repb])
low high repa] =
hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb]"
by (simp add: isLeaf_pt_def repNodes_eq_def null_comp_def)
from hd_term_in_take_Sucn
have "[sn\<leftarrow>(prx@[node]). repNodes_eq sn
(hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have "hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb] =
hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb]"
apply -
apply (rule hd_filter_app [symmetric])
apply auto
done
then have hd_term_nodeslist_Sucn:
"hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb] =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb]"
by simp
from no_in_take_Sucn filter_Sucn_no_notempty
have filter_filter: "hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn
(hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb] =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
apply -
apply (rule filter_hd_P_rep_indep)
apply (auto simp add: repNodes_eq_def)
done
from repb_no_def repb_no_nln repb_node
have "repb (repb no) = hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repa]"
by simp
with nested_hd_repa_repb
have "repb (repb no) = hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn
(hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb]"
by simp
with hd_term_nodeslist_Sucn
have "repb (repb no) = hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn
( hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb])
low high repb]"
by simp
with filter_filter
have "repb (repb no) = hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn no low high repb]"
by simp
with repb_no_def show ?thesis
by simp
qed
have two_nodes_repb: "(\<forall>no1\<in>set (prx@[node]).
((repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1))"
proof (intro ballI)
fix no1
assume no1_in_take_Sucn: " no1 \<in> set (prx@[node])"
then have "no1 \<in> set (prx@node#sfx)" by auto
with all_nodes_in_nl_Leafs
have isLeaf_no1: "isLeaf_pt no1 low high"
by auto
with isLeaf_no
have repbchildren_eq_no_no1: "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
by (simp add: null_comp_def isLeaf_pt_def)
from isLeaf_no1 isLeaf_no
have repachildren_eq_no_no1: "(repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no"
by (simp add: null_comp_def isLeaf_pt_def)
from while_low_Null
have while_low_same_rep: "(\<forall>no1\<in>set prx.
((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1))"
by auto
show "((repb \<propto> high) no1 = (repb \<propto> high) no \<and>
(repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1)"
proof (cases "no1 = node")
case False
with no1_in_take_Sucn have "no1 \<in> set prx"
by auto
with while_low_same_rep repachildren_eq_no_no1
have "repa no = repa no1"
by auto
with repa_repb_nc no_notin_nl False repbchildren_eq_no_no1
show ?thesis
by auto
next
assume no1_nln: "no1 = node"
hence no1_in_take_Sucn: "no1 \<in> set (prx@[node])"
by auto
hence no1_in_nl: "no1 \<in> set (prx@node#sfx)"
by auto
from nodes_balanced_ordered [rule_format, OF this] have
balanced_no1: "(low no1 = Null) = (high no1 = Null)"
by auto
with no1_in_take_Sucn repb_no_share_def isLeaf_no1
have repb_no1: "repb no1 = hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn no1 low high repb]"
by (auto simp add: isLeaf_pt_def)
from balanced_no1 isLeaf_no1 isLeaf_no balanced_no
have repbchildren_eq_no1_no: "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
by (simp add: null_comp_def isLeaf_pt_def)
have "\<forall> x \<in> set (prx@[node]). repNodes_eq x no low high repb
= repNodes_eq x no1 low high repb"
proof (intro ballI)
fix x
assume x_in_take_Sucn: " x \<in> set (prx@[node])"
with repbchildren_eq_no1_no show "repNodes_eq x no low high repb
= repNodes_eq x no1 low high repb"
by (simp add: repNodes_eq_def)
qed
then have " [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]
= [sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb]"
by (rule P_eq_list_filter)
with repb_no_def repb_no1 have repb_no_no1: "repb no = repb no1"
by simp
with repbchildren_eq_no1_no show ?thesis
by simp
qed
qed
with repb_repb_no repb_no_share_def no_in_take_Sucn share_case_repb
show ?thesis
using [[simp_depth_limit=4]]
by auto
next
assume lno_nNull: "low no \<noteq> Null"
with share_case_repb
have repbchildren_neq_no: "(repb \<propto> low) no \<noteq> (repb \<propto> high) no"
by auto
from balanced_no lno_nNull
have hno_nNull: "high no \<noteq> Null"
by simp
with repbchildren_neq_no lno_nNull repa_repb_nc
lno_notin_nl hno_notin_nl nodes_notin_nl_neq_nln
have repachildren_neq_no: "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
using [[simp_depth_limit=2]]
by (auto simp add: null_comp_def)
with while_share_red_exp
have repa_while_inv: "repa (repa no) = repa no
\<and> (\<forall>no1\<in>set prx. ((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1))"
by auto
from lno_nNull hno_nNull
have no_nLeaf: "\<not> isLeaf_pt no low high"
by (simp add: isLeaf_pt_def)
have all_nodes_in_nl_nLeafs:
"\<forall>x \<in> set (prx@node#sfx). \<not> isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nodeslist: " x \<in> set (prx@node#sfx)"
from no_nLeaf isLeaf_var_no have "1 < var no "
by simp
with all_nodes_same_var [rule_format, OF x_in_nodeslist no_in_nl]
have "1 < var x"
by simp
with nodes_balanced_ordered [rule_format, OF x_in_nodeslist]
show " \<not> isLeaf_pt x low high"
using [[simp_depth_limit = 2]]
by (auto simp add: isLeaf_pt_def)
qed
have repb_repb_no: "repb (repb no) = repb no"
proof -
from repa_while_inv no_notin_nl repa_repb_nc
have "repa (repb no) = repb no"
by simp
from hd_filter_Sucn_in_Sucn repb_no_def
have repb_no_in_take_Sucn: "repb no \<in> set (prx@[node])"
by simp
hence repb_no_in_nl: "repb no \<in> set (prx@node#sfx)"
by auto
from all_nodes_in_nl_nLeafs repb_no_in_nl
have repb_no_nLeaf: "\<not> isLeaf_pt (repb no) low high"
by auto
from nodes_balanced_ordered [rule_format, OF repb_no_in_nl]
have "(low (repb no) = Null) = (high (repb no) = Null)
\<and> low (repb no) \<notin> set (prx@node#sfx) \<and>
high (repb no) \<notin> set (prx@node#sfx)"
by auto
from filter_take_Sucn_not_empty
have " repNodes_eq (hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn no low high repb]) no low high repb"
by (rule hd_filter_prop)
with repb_no_def have "repNodes_eq (repb no) no low high repb"
by simp
then have "(repb \<propto> low) (repb no) = (repb \<propto> low) no
\<and> (repb \<propto> high) (repb no) = (repb \<propto> high) no"
by (simp add: repNodes_eq_def)
with repbchildren_neq_no have "(repb \<propto> low) (repb no)
\<noteq> (repb \<propto> high) (repb no)"
by simp
with repb_no_in_take_Sucn repb_no_share_def
have repb_repb_no_double_hd:
"repb (repb no) = hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn (repb no) low high repb]"
by auto
from filter_take_Sucn_not_empty
have " hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn (repb no) low high repb] = repb no"
apply (simp only: repb_no_def )
apply (rule filter_hd_P_rep_indep)
apply (auto simp add: repNodes_eq_def)
done
with repb_repb_no_double_hd show ?thesis
by simp
qed
have "(\<forall>no1\<in>set (prx@[node]).
((repb \<propto> high) no1 = (repb \<propto> high) no \<and>
(repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1))"
proof (intro ballI)
fix no1
assume no1_in_take_Sucn: "no1 \<in> set (prx@[node])"
hence no1_in_nl: "no1 \<in> set (prx@node#sfx)"
by auto
from all_nodes_in_nl_nLeafs no1_in_nl
have no1_nLeaf: "\<not> isLeaf_pt no1 low high"
by auto
from nodes_balanced_ordered [rule_format, OF no1_in_nl]
have no1_props: "(low no1 = Null) = (high no1 = Null)
\<and> low no1 \<notin> set (prx@node#sfx) \<and> high no1 \<notin> set (prx@node#sfx)"
by auto
show "((repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1)"
proof (cases "no1 = node")
case False
note no1_neq_nln=this
with no1_in_take_Sucn
have no1_in_take_n: "no1 \<in> set prx"
by auto
with repa_while_inv have "((repa \<propto> high) no1 = (repa \<propto> high) no
\<and> (repa \<propto> low) no1 = (repa \<propto> low) no) = (repa no = repa no1)"
by fastforce
with no1_props no1_nLeaf no_nLeaf balanced_no lno_notin_nl
hno_notin_nl nodes_notin_nl_neq_nln no_notin_nl
no1_neq_nln repa_repb_nc
show ?thesis
using [[simp_depth_limit=1]]
by (auto simp add: null_comp_def isLeaf_pt_def)
next
assume no1_nln: " no1 = node"
show ?thesis
proof
assume repbchildren_eq_no1_no:
"(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
with repbchildren_neq_no
have "(repb \<propto> high) no1 \<noteq> (repb \<propto> low) no1"
by auto
with repb_no_share_def no1_in_take_Sucn
have repb_no1_def: " repb no1 = hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn no1 low high repb]"
by auto
have filter_no1_eq_filter_no: "[sn\<leftarrow>(prx@[node]).
repNodes_eq sn no1 low high repb] =
[sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
proof -
have "\<forall>x \<in> set (prx@[node]).
repNodes_eq x no1 low high repb =
repNodes_eq x no low high repb"
proof (intro ballI)
fix x
assume x_in_take_Sucn: "x \<in> set (prx@[node])"
with repbchildren_eq_no1_no
show "repNodes_eq x no1 low high repb =
repNodes_eq x no low high repb"
by (simp add: repNodes_eq_def)
qed
then show ?thesis
by (rule P_eq_list_filter)
qed
with repb_no1_def repb_no_def show " repb no = repb no1"
by simp
next
assume repb_no_no1_eq: "repb no = repb no1"
from no1_nln repb_node repb_no_def have repb_no1_def:
"repb no1 =
hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn node low high repa]"
by auto
with no1_nln repb_no_def repb_no_no1_eq
have repb_Sucn_repa_nl_hd: " hd [sn\<leftarrow>(prx@[node]).
repNodes_eq sn no low high repb] =
hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no1 low high repa]"
by simp
from filter_take_Sucn_not_empty
have " hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]
= hd [sn\<leftarrow>(prx@node#sfx) . repNodes_eq sn no low high repb]"
apply -
apply (rule hd_filter_app [symmetric])
apply auto
done
then have hd_Sucn_hd_whole_list:
"hd [sn\<leftarrow>(prx@[node]) .
repNodes_eq sn no low high repb] =
hd [sn\<leftarrow> (prx@node#sfx). repNodes_eq sn no low high repb]"
by simp
have hd_nl_repb_repa:
"[sn\<leftarrow> (prx@node#sfx). repNodes_eq sn no low high repb]
= [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa]"
proof -
have "\<forall>x \<in> set (prx@node#sfx).
repNodes_eq x no low high repb =
repNodes_eq x no low high repa"
proof (intro ballI)
fix x
assume x_in_nl: "x \<in> set (prx@node#sfx)"
from all_nodes_in_nl_nLeafs x_in_nl
have x_nLeaf: "\<not> isLeaf_pt x low high"
by auto
from nodes_balanced_ordered [rule_format, OF x_in_nl]
have x_props: "(low x = Null) = (high x = Null) \<and>
low x \<notin> set (prx@node#sfx) \<and> high x \<notin> set (prx@node#sfx)"
by auto
with x_nLeaf lno_nNull hno_nNull lno_notin_nl hno_notin_nl
nodes_notin_nl_neq_nln repa_repb_nc
show "repNodes_eq x no low high repb =
repNodes_eq x no low high repa"
using [[simp_depth_limit=1]]
by (simp add: repNodes_eq_def isLeaf_pt_def null_comp_def)
qed
then show ?thesis
by (rule P_eq_list_filter)
qed
with repb_Sucn_repa_nl_hd hd_Sucn_hd_whole_list
have filter_nl_no_no1:
"hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa]
= hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no1 low high repa]"
by simp
from no_in_nl have filter_no_not_empty:
"[sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
from no1_in_nl have filter_no1_not_empty:
"[sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no1 low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
from repb_no_def hd_Sucn_hd_whole_list hd_nl_repb_repa
have "repb no =
hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa]"
by simp
with hd_filter_prop [OF filter_no_not_empty ]
have repNodes_no_repa: "repNodes_eq (repb no) no low high repa"
by auto
from repb_no1_def no1_nln
have
"repb no1 = hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no1
low high repa]"
by simp
with hd_filter_prop [OF filter_no1_not_empty ]
have "repNodes_eq (repb no1) no1 low high repa"
by auto
with filter_nl_no_no1 repNodes_no_repa repb_no_no1_eq
have "(repa \<propto> high) no1 =
(repa \<propto> high) no \<and> (repa \<propto> low) no1 = (repa \<propto> low) no"
by (simp add: repNodes_eq_def)
with hno_nNull no1_props no1_nLeaf lno_nNull lno_notin_nl
hno_notin_nl nodes_notin_nl_neq_nln repa_repb_nc
show "(repb \<propto> high) no1 =
(repb \<propto> high) no \<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
using [[simp_depth_limit=1]]
by (auto simp add: isLeaf_pt_def null_comp_def)
qed
qed
qed
with repb_repb_no repb_no_share_def share_case_repb no_in_take_Sucn
show ?thesis
using [[simp_depth_limit=1]]
by auto
qed
qed
with repb_no_nNull show ?thesis
by simp
next
assume no_nln: "no = node"
with repb_node have repb_no_def:
"repb no = hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa]"
by simp
from no_nln have "no \<in> set (prx@node#sfx)"
by auto
then have filter_nl_repa_not_empty:
"[sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then have hd_filter_nl_in_nl:
"hd [sn\<leftarrow>(prx@node#sfx). repNodes_eq sn no low high repa] \<in> set (prx@node#sfx)"
by (rule hd_filter_in_list)
with repb_no_def
have repb_no_in_nodeslist: "repb no \<in> set (prx@node#sfx)"
by simp
from nodes_balanced_ordered [rule_format,OF this]
have repb_no_nNull: "repb no \<noteq> Null"
by auto
from share_cond no_nln have share_cond_or:
"isLeaf_pt no low high \<or> repa (low no) \<noteq> repa (high no)"
by auto
have share_reduce_if: " (if (repb \<propto> low) no = (repb \<propto> high) no \<and> low no \<noteq> Null
then repb no = (repb \<propto> low) no
else repb no = hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb] \<and>
repb (repb no) = repb no
\<and> (\<forall>no1\<in>set (prx@[node]). ((repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1)))"
proof (cases "isLeaf_pt no low high")
case True
note isLeaf_no=this
then have lno_Null: "low no = Null" by (simp add: isLeaf_pt_def)
from isLeaf_no no_in_take_Sucn repb_no_share_def
have repb_no_repb_def: "repb no
= hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
by (auto simp add: isLeaf_pt_def)
from isLeaf_no nodes_balanced_ordered [rule_format, OF no_in_nl]
have var_no: "var no \<le> 1"
by auto
have all_nodes_nl_var_l_1: "\<forall>x \<in> set (prx@node#sfx). var x \<le> 1"
proof (intro ballI)
fix x
assume x_in_nl: " x \<in> set (prx@node#sfx)"
from all_nodes_same_var [rule_format, OF x_in_nl no_in_nl] var_no
show " var x \<le> 1"
by auto
qed
have all_nodes_nl_Leafs: "\<forall>x \<in> set (prx@node#sfx). isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nl: " x \<in> set (prx@node#sfx)"
with all_nodes_nl_var_l_1 have "var x \<le> 1"
by auto
with nodes_balanced_ordered [rule_format, OF x_in_nl ]
show "isLeaf_pt x low high"
by auto
qed
have repb_repb_no: "repb (repb no) = repb no"
proof -
from repb_no_share_def no_in_take_Sucn lno_Null
have repb_no_def: " repb no =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
by auto
with hd_filter_Sucn_in_Sucn
have repb_no_in_take_Sucn: "repb no \<in> set (prx@[node])"
by simp
hence repb_no_in_nl: "repb no \<in> set (prx@[node])"
by auto
with all_nodes_nl_Leafs
have repb_no_Leaf: "isLeaf_pt (repb no) low high"
by auto
with repb_no_in_take_Sucn repb_no_share_def
have repb_repb_no_def: "repb (repb no) =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn (repb no) low high repb] "
by (auto simp add: isLeaf_pt_def)
from filter_take_Sucn_not_empty
show ?thesis
apply (simp only: repb_repb_no_def )
apply (simp only: repb_no_def)
apply (rule filter_hd_P_rep_indep)
apply (auto simp add: repNodes_eq_def)
done
qed
have two_nodes_repb: "(\<forall>no1\<in>set (prx@[node]).
((repb \<propto> high) no1 = (repb \<propto> high) no \<and>
(repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1))"
proof (intro ballI)
fix no1
assume no1_in_take_Sucn: "no1 \<in> set (prx@[node])"
from no1_in_take_Sucn
have "no1 \<in> set (prx@node#sfx)"
by auto
with all_nodes_nl_Leafs
have isLeaf_no1: "isLeaf_pt no1 low high"
by auto
with repb_no_share_def no1_in_take_Sucn
have repb_no1_def: "repb no1 =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb]"
by (auto simp add: isLeaf_pt_def)
show "((repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1)"
proof
assume repbchildren_eq_no1_no: "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
have "[sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb]
= [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
proof -
have "\<forall>x \<in> set (prx@[node]).
repNodes_eq x no1 low high repb = repNodes_eq x no low high repb"
proof (intro ballI)
fix x
assume x_in_take_Sucn: " x \<in> set (prx@[node])"
with repbchildren_eq_no1_no
show " repNodes_eq x no1 low high repb = repNodes_eq x no low high repb"
by (simp add: repNodes_eq_def)
qed
then show ?thesis
by (rule P_eq_list_filter)
qed
with repb_no1_def repb_no_repb_def
show "repb no = repb no1"
by simp
next
assume repb_no_no1: "repb no = repb no1"
with isLeaf_no isLeaf_no1
show "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
by (simp add: null_comp_def isLeaf_pt_def)
qed
qed
with repb_repb_no lno_Null no_in_take_Sucn repb_no_share_def show ?thesis
by auto
next
assume no_nLeaf: "\<not> isLeaf_pt no low high"
with balanced_no obtain
lno_nNull: "low no \<noteq> Null" and
hno_nNull: "high no \<noteq> Null"
by (simp add: isLeaf_pt_def)
from no_nLeaf nodes_balanced_ordered [rule_format, OF no_in_nl]
have var_no: "1 < var no"
by auto
have all_nodes_nl_var_l_1: "\<forall>x \<in> set (prx@node#sfx). 1 < var x"
proof (intro ballI)
fix x
assume x_in_nl: " x \<in> set (prx@node#sfx)"
with all_nodes_same_var [rule_format, OF x_in_nl no_in_nl] var_no
show "1 < var x"
by simp
qed
have all_nodes_nl_nLeafs: "\<forall> x \<in> set (prx@node#sfx). \<not> isLeaf_pt x low high"
proof (intro ballI)
fix x
assume x_in_nl: " x \<in> set (prx@node#sfx)"
with all_nodes_nl_var_l_1 have "1 < var x"
by auto
with nodes_balanced_ordered [rule_format, OF x_in_nl] show " \<not> isLeaf_pt x low high"
by auto
qed
from no_nLeaf share_cond_or
have repachildren_neq_no: "repa (low no) \<noteq> repa (high no)"
by auto
with lno_nNull hno_nNull
have "(repa \<propto> low) no \<noteq> (repa \<propto> high) no"
by (simp add: null_comp_def)
with repa_repb_nc lno_notin_nl hno_notin_nl
nodes_notin_nl_neq_nln lno_nNull hno_nNull
have repbchildren_neq_no: "(repb \<propto> low) no \<noteq> (repb \<propto> high) no"
using [[simp_depth_limit=1]]
by (auto simp add: null_comp_def)
have repb_repb_no: "repb (repb no) = repb no"
proof -
from repb_no_share_def no_in_take_Sucn repbchildren_neq_no
have repb_no_def: "repb no =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
by auto
from filter_take_Sucn_not_empty
have "repNodes_eq (repb no) no low high repb"
apply (simp only: repb_no_def)
apply (rule hd_filter_prop)
apply simp
done
with repbchildren_neq_no
have repbchildren_neq_repb_no: "(repb \<propto> low) (repb no) \<noteq> (repb \<propto> high) (repb no)"
by (simp add: repNodes_eq_def)
from filter_take_Sucn_not_empty
have "repb no \<in> set (prx@[node])"
apply (simp only: repb_no_def )
apply (rule hd_filter_in_list)
apply simp
done
with repbchildren_neq_repb_no repb_no_share_def
have repb_repb_no_def: " repb (repb no) =
hd [sn\<leftarrow>(prx@[node]) . repNodes_eq sn (repb no) low high repb] "
by auto
from filter_take_Sucn_not_empty show ?thesis
apply (simp only: repb_repb_no_def )
apply (simp only: repb_no_def)
apply (rule filter_hd_P_rep_indep)
apply (auto simp add: repNodes_eq_def)
done
qed
have two_nodes_repb: "(\<forall>no1\<in>set (prx@[node]).
((repb \<propto> high) no1 = (repb \<propto> high) no \<and>
(repb \<propto> low) no1 = (repb \<propto> low) no) = (repb no = repb no1))"
(is "(\<forall>no1\<in>set (prx@[node]). ?P no1)")
proof (intro ballI)
fix no1
assume no1_in_take_Sucn: " no1 \<in> set (prx@[node])"
hence no1_in_nodeslist: "no1 \<in> set (prx@node#sfx)"
by auto
with all_nodes_nl_nLeafs
have no1_nLeaf: "\<not> isLeaf_pt no1 low high"
by auto
show "?P no1"
proof
assume repbchildren_eq_no1_no: "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
with repbchildren_neq_no have "(repb \<propto> high) no1 \<noteq> (repb \<propto> low) no1"
by auto
with no1_in_take_Sucn repb_no_share_def have repb_no1_def: "repb no1 =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb]"
by auto
from repb_no_share_def no_in_take_Sucn repbchildren_neq_no
have repb_no_def: "repb no =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
by auto
have "[sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb] =
[sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
proof -
have "\<forall> x \<in> set (prx@[node]).
repNodes_eq x no1 low high repb = repNodes_eq x no low high repb"
proof (intro ballI)
fix x
assume x_in_take_Sucn: " x \<in> set (prx@[node])"
with repbchildren_eq_no1_no
show " repNodes_eq x no1 low high repb = repNodes_eq x no low high repb"
by (simp add: repNodes_eq_def)
qed
then show ?thesis
by (rule P_eq_list_filter)
qed
with repb_no_def repb_no1_def show " repb no = repb no1"
by simp
next
assume repb_no_no1: "repb no = repb no1"
from repb_no_share_def no_in_take_Sucn repbchildren_neq_no
have repb_no_def: "repb no =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no low high repb]"
by auto
from filter_take_Sucn_not_empty
have "repb no \<in> set (prx@[node])"
apply (simp only: repb_no_def)
apply (rule hd_filter_in_list)
apply simp
done
then have repb_no_in_nl: "repb no \<in> set (prx@node#sfx)"
by auto
from filter_take_Sucn_not_empty
have repNodes_repb_no: "repNodes_eq (repb no) no low high repb"
apply (simp only: repb_no_def)
apply (rule hd_filter_prop)
apply simp
done
show "(repb \<propto> high) no1 = (repb \<propto> high) no
\<and> (repb \<propto> low) no1 = (repb \<propto> low) no"
proof (cases "(repb \<propto> low) no1 = (repb \<propto> high) no1")
case True
note red_cond=this
from no1_in_nodeslist all_nodes_nl_nLeafs
have no1_nLeaf: "\<not> isLeaf_pt no1 low high"
by auto
from nodes_balanced_ordered [rule_format, OF no1_in_nodeslist]
have no1_props: "(low no1 \<notin> set (prx@node#sfx))
\<and> (high no1 \<notin> set (prx@node#sfx)) \<and>(low no1 = Null) = (high no1 = Null)
\<and> ((rep \<propto> low) no1 \<notin> set (prx@node#sfx))"
by auto
with red_cond no1_nLeaf no1_in_take_Sucn repb_no_red_def
have repb_no1_def: "repb no1 = (repb \<propto> low) no1"
by (auto simp add: isLeaf_pt_def)
with no1_nLeaf no1_props have "repb no1 = repb (low no1)"
by (simp add: null_comp_def isLeaf_pt_def)
from no1_props no1_nLeaf have "rep (low no1) \<notin> set (prx@node#sfx)"
by (auto simp add: isLeaf_pt_def null_comp_def)
with rep_repb_nc no1_props
have "repb (low no1) \<notin> set (prx@node#sfx)"
by auto
with repb_no1_def repb_no_no1 no1_props no1_nLeaf
have "repb no \<notin> set (prx@node#sfx)"
by (simp add: isLeaf_pt_def null_comp_def)
with repb_no_in_nl show ?thesis
by simp
next
assume "(repb \<propto> low) no1 \<noteq> (repb \<propto> high) no1"
with repb_no_share_def no1_in_take_Sucn
have repb_no1_def: " repb no1 =
hd [sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb]"
by auto
from no1_in_take_Sucn
have "[sn\<leftarrow>(prx@[node]). repNodes_eq sn no1 low high repb] \<noteq> []"
apply -
apply (rule filter_not_empty)
apply (auto simp add: repNodes_eq_def)
done
then
have repNodes_repb_no1: "repNodes_eq (repb no1) no1 low high repb"
apply (simp only: repb_no1_def )
apply (rule hd_filter_prop)
apply simp
done
with repNodes_repb_no repb_no_no1
have "repNodes_eq no1 no low high repb"
by (simp add: repNodes_eq_def)
then show ?thesis
by (simp add: repNodes_eq_def)
qed
qed
qed
with repb_repb_no repb_no_share_def no_in_take_Sucn repbchildren_neq_no
show ?thesis
using [[simp_depth_limit=2]]
by fastforce
qed
with repb_no_nNull show ?thesis
by simp
qed
qed
with rep_repb_nc show ?thesis
by (intro conjI)
qed
qed
end