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-rw-r--r--theories/Sorting/Sorting.v124
1 files changed, 3 insertions, 121 deletions
diff --git a/theories/Sorting/Sorting.v b/theories/Sorting/Sorting.v
index aed8cd15..5f8da6a4 100644
--- a/theories/Sorting/Sorting.v
+++ b/theories/Sorting/Sorting.v
@@ -6,125 +6,7 @@
(* * GNU Lesser General Public License Version 2.1 *)
(************************************************************************)
-(*i $Id: Sorting.v 10698 2008-03-19 18:46:59Z letouzey $ i*)
+(*i $Id$ i*)
-Require Import List Multiset Permutation Relations.
-
-Set Implicit Arguments.
-
-Section defs.
-
- Variable A : Type.
- Variable leA : relation A.
- Variable eqA : relation A.
-
- Let gtA (x y:A) := ~ leA x y.
-
- Hypothesis leA_dec : forall x y:A, {leA x y} + {leA y x}.
- Hypothesis eqA_dec : forall x y:A, {eqA x y} + {~ eqA x y}.
- Hypothesis leA_refl : forall x y:A, eqA x y -> leA x y.
- Hypothesis leA_trans : forall x y z:A, leA x y -> leA y z -> leA x z.
- Hypothesis leA_antisym : forall x y:A, leA x y -> leA y x -> eqA x y.
-
- Hint Resolve leA_refl.
- Hint Immediate eqA_dec leA_dec leA_antisym.
-
- Let emptyBag := EmptyBag A.
- Let singletonBag := SingletonBag _ eqA_dec.
-
- (** [lelistA] *)
-
- Inductive lelistA (a:A) : list A -> Prop :=
- | nil_leA : lelistA a nil
- | cons_leA : forall (b:A) (l:list A), leA a b -> lelistA a (b :: l).
-
- Lemma lelistA_inv : forall (a b:A) (l:list A), lelistA a (b :: l) -> leA a b.
- Proof.
- intros; inversion H; trivial with datatypes.
- Qed.
-
- (** * Definition for a list to be sorted *)
-
- Inductive sort : list A -> Prop :=
- | nil_sort : sort nil
- | cons_sort :
- forall (a:A) (l:list A), sort l -> lelistA a l -> sort (a :: l).
-
- Lemma sort_inv :
- forall (a:A) (l:list A), sort (a :: l) -> sort l /\ lelistA a l.
- Proof.
- intros; inversion H; auto with datatypes.
- Qed.
-
- Lemma sort_rect :
- forall P:list A -> Type,
- P nil ->
- (forall (a:A) (l:list A), sort l -> P l -> lelistA a l -> P (a :: l)) ->
- forall y:list A, sort y -> P y.
- Proof.
- simple induction y; auto with datatypes.
- intros; elim (sort_inv (a:=a) (l:=l)); auto with datatypes.
- Qed.
-
- Lemma sort_rec :
- forall P:list A -> Set,
- P nil ->
- (forall (a:A) (l:list A), sort l -> P l -> lelistA a l -> P (a :: l)) ->
- forall y:list A, sort y -> P y.
- Proof.
- simple induction y; auto with datatypes.
- intros; elim (sort_inv (a:=a) (l:=l)); auto with datatypes.
- Qed.
-
- (** * Merging two sorted lists *)
-
- Inductive merge_lem (l1 l2:list A) : Type :=
- merge_exist :
- forall l:list A,
- sort l ->
- meq (list_contents _ eqA_dec l)
- (munion (list_contents _ eqA_dec l1) (list_contents _ eqA_dec l2)) ->
- (forall a:A, lelistA a l1 -> lelistA a l2 -> lelistA a l) ->
- merge_lem l1 l2.
-
- Lemma merge :
- forall l1:list A, sort l1 -> forall l2:list A, sort l2 -> merge_lem l1 l2.
- Proof.
- simple induction 1; intros.
- apply merge_exist with l2; auto with datatypes.
- elim H2; intros.
- apply merge_exist with (a :: l); simpl in |- *; auto using cons_sort with datatypes.
- elim (leA_dec a a0); intros.
-
- (* 1 (leA a a0) *)
- cut (merge_lem l (a0 :: l0)); auto using cons_sort with datatypes.
- intros [l3 l3sorted l3contents Hrec].
- apply merge_exist with (a :: l3); simpl in |- *;
- auto using cons_sort, cons_leA with datatypes.
- apply meq_trans with
- (munion (singletonBag a)
- (munion (list_contents _ eqA_dec l)
- (list_contents _ eqA_dec (a0 :: l0)))).
- apply meq_right; trivial with datatypes.
- apply meq_sym; apply munion_ass.
- intros; apply cons_leA.
- apply lelistA_inv with l; trivial with datatypes.
-
- (* 2 (leA a0 a) *)
- elim X0; simpl in |- *; intros.
- apply merge_exist with (a0 :: l3); simpl in |- *;
- auto using cons_sort, cons_leA with datatypes.
- apply meq_trans with
- (munion (singletonBag a0)
- (munion (munion (singletonBag a) (list_contents _ eqA_dec l))
- (list_contents _ eqA_dec l0))).
- apply meq_right; trivial with datatypes.
- apply munion_perm_left.
- intros; apply cons_leA; apply lelistA_inv with l0; trivial with datatypes.
- Qed.
-
-End defs.
-
-Unset Implicit Arguments.
-Hint Constructors sort: datatypes v62.
-Hint Constructors lelistA: datatypes v62.
+Require Export Sorted.
+Require Export Mergesort.