Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Inductive proof:Set :=
  Ax : positive -> proof
| I_Arrow : proof -> proof
| E_Arrow : positive -> positive -> proof -> proof
| D_Arrow : positive -> proof -> proof -> proof
| E_False : positive -> proof
| I_And: proof -> proof -> proof
| E_And: positive -> proof -> proof
| D_And: positive -> proof -> proof
| I_Or_l: proof -> proof
| I_Or_r: proof -> proof
| E_Or: positive -> proof -> proof -> proof
| D_Or: positive -> proof -> proof
| Cut: form -> proof -> proof -> proof.Notation "hyps \ A" := (push A hyps) (at level 72,left associativity).Fixpoint check_proof (hyps:ctx) (gl:form) (P:proof) {struct P}: bool :=
 match P with
   Ax i =>
     match get i hyps with
         PSome F => form_eq F gl
 | _ => false
    end
| I_Arrow p =>
   match gl with
      A  =>> B  => check_proof (hyps \ A) B p
   | _ => false
    end
| E_Arrow i j p =>
   match get i hyps,get j hyps with
       PSome A,PSome (B =>>C) =>
         form_eq A B && check_proof (hyps \ C) (gl) p
    | _,_ => false
    end
| D_Arrow i p1 p2 =>
   match get i hyps with
      PSome  ((A =>>B)=>>C) =>
     (check_proof ( hyps \ B =>> C \ A) B p1) && (check_proof (hyps \ C) gl p2)
    | _ => false
  end
| E_False i =>
  match get i hyps with
    PSome # => true
  | _ => false
  end
| I_And p1 p2 =>
   match gl with
      A //\\ B =>
      check_proof hyps A p1 && check_proof hyps B p2
      | _ => false
      end
| E_And i p =>
   match get i hyps with
      PSome  (A //\\ B) => check_proof (hyps \ A \ B) gl p
    | _=> false
   end
| D_And i p =>
   match get i hyps with
      PSome  (A //\\ B =>> C) => check_proof (hyps \ A=>>B=>>C) gl p
    | _=> false
   end
| I_Or_l p =>
   match gl with
      (A \\// B) => check_proof hyps A p
      | _ => false
      end
| I_Or_r p =>
   match gl with
      (A \\// B) => check_proof hyps B p
      | _ => false
      end
| E_Or i p1 p2 =>
  match get i hyps with
  PSome (A \\// B) =>
  check_proof (hyps \ A) gl p1 && check_proof (hyps \ B) gl p2
  | _=> false
  end
| D_Or i p =>
   match get i hyps with
      PSome  (A \\// B =>> C) =>
      (check_proof (hyps \ A=>>C \ B=>>C) gl p)
    | _=> false
   end
| Cut A p1 p2 =>
  check_proof hyps A p1 && check_proof (hyps \ A) gl p2
end.

Theorem Reflect: forall gl prf, if check_proof empty gl prf then [[gl]] else True.