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(* 02110-1301 USA                                                     *)
(********************************************************************** Proof of Huffman algorithm: Aux.v  Auxillary functions & Theorems  Definitions: le_bool, map2, first_n, skip_n find_min find_max  Theorems: minus, map, app  Laurent.Thery@inria.fr (2003) **********************************************************************)
Require Export List.
Require Export Arith.
From Huffman Require Export sTactic.
(* Some facts about the minus operator *)
Section Minus.

Theorem lt_minus_O : forall n m, m < n -> 0 < n - m.
Proof using.