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Diffstat (limited to 'contrib7/correctness/Exchange.v')
-rw-r--r-- | contrib7/correctness/Exchange.v | 94 |
1 files changed, 0 insertions, 94 deletions
diff --git a/contrib7/correctness/Exchange.v b/contrib7/correctness/Exchange.v deleted file mode 100644 index 12c8c9de..00000000 --- a/contrib7/correctness/Exchange.v +++ /dev/null @@ -1,94 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) -(* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) -(************************************************************************) - -(* Certification of Imperative Programs / Jean-Christophe Filliātre *) - -(* $Id: Exchange.v,v 1.1.2.1 2004/07/16 19:30:16 herbelin Exp $ *) - -(****************************************************************************) -(* Exchange of two elements in an array *) -(* Definition and properties *) -(****************************************************************************) - -Require ProgInt. -Require Arrays. - -Set Implicit Arguments. - -(* Definition *) - -Inductive exchange [n:Z; A:Set; t,t':(array n A); i,j:Z] : Prop := - exchange_c : - `0<=i<n` -> `0<=j<n` -> - (#t[i] = #t'[j]) -> - (#t[j] = #t'[i]) -> - ((k:Z)`0<=k<n` -> `k<>i` -> `k<>j` -> #t[k] = #t'[k]) -> - (exchange t t' i j). - -(* Properties about exchanges *) - -Lemma exchange_1 : (n:Z)(A:Set)(t:(array n A)) - (i,j:Z) `0<=i<n` -> `0<=j<n` -> - (access (store (store t i #t[j]) j #t[i]) i) = #t[j]. -Proof. -Intros n A t i j H_i H_j. -Case (dec_eq j i). -Intro eq_i_j. Rewrite eq_i_j. -Auto with datatypes. -Intro not_j_i. -Rewrite (store_def_2 (store t i #t[j]) #t[i] H_j H_i not_j_i). -Auto with datatypes. -Save. - -Hints Resolve exchange_1 : v62 datatypes. - - -Lemma exchange_proof : - (n:Z)(A:Set)(t:(array n A)) - (i,j:Z) `0<=i<n` -> `0<=j<n` -> - (exchange (store (store t i (access t j)) j (access t i)) t i j). -Proof. -Intros n A t i j H_i H_j. -Apply exchange_c; Auto with datatypes. -Intros k H_k not_k_i not_k_j. -Cut ~j=k; Auto with datatypes. Intro not_j_k. -Rewrite (store_def_2 (store t i (access t j)) (access t i) H_j H_k not_j_k). -Auto with datatypes. -Save. - -Hints Resolve exchange_proof : v62 datatypes. - - -Lemma exchange_sym : - (n:Z)(A:Set)(t,t':(array n A))(i,j:Z) - (exchange t t' i j) -> (exchange t' t i j). -Proof. -Intros n A t t' i j H1. -Elim H1. Clear H1. Intros. -Constructor 1; Auto with datatypes. -Intros. Rewrite (H3 k); Auto with datatypes. -Save. - -Hints Resolve exchange_sym : v62 datatypes. - - -Lemma exchange_id : - (n:Z)(A:Set)(t,t':(array n A))(i,j:Z) - (exchange t t' i j) -> - i=j -> - (k:Z) `0 <= k < n` -> (access t k)=(access t' k). -Proof. -Intros n A t t' i j Hex Heq k Hk. -Elim Hex. Clear Hex. Intros. -Rewrite Heq in H1. Rewrite Heq in H2. -Case (Z_eq_dec k j). - Intro Heq'. Rewrite Heq'. Assumption. - Intro Hnoteq. Apply (H3 k); Auto with datatypes. Rewrite Heq. Assumption. -Save. - -Hints Resolve exchange_id : v62 datatypes. |