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authorGravatar Jason Gross <jgross@mit.edu>2016-06-10 15:01:26 -0400
committerGravatar Jason Gross <jgross@mit.edu>2016-06-10 15:03:07 -0400
commit8d4f4adf80c7fdaa8021b283526ab1592ee13600 (patch)
treead05d7c38469aefd74ad9f54a5621099a1bd351f /coqprime-8.5/Coqprime/Permutation.v
parent2e566c32baf2a140cd7820c4f06437ee5c43ac44 (diff)
Add coqprime that works with 8.5, bundle bedrock
This simplifes the build process, and also allows us to try to build with 8.5. We autodetect the version of Coq in the Makefile to decide which version of coqprime to build.
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+
+(*************************************************************)
+(* This file is distributed under the terms of the *)
+(* GNU Lesser General Public License Version 2.1 *)
+(*************************************************************)
+(* Benjamin.Gregoire@inria.fr Laurent.Thery@inria.fr *)
+(*************************************************************)
+
+(**********************************************************************
+ Permutation.v
+
+ Defintion and properties of permutations
+ **********************************************************************)
+Require Export List.
+Require Export ListAux.
+
+Section permutation.
+Variable A : Set.
+
+(**************************************
+ Definition of permutations as sequences of adjacent transpositions
+ **************************************)
+
+Inductive permutation : list A -> list A -> Prop :=
+ | permutation_nil : permutation nil nil
+ | permutation_skip :
+ forall (a : A) (l1 l2 : list A),
+ permutation l2 l1 -> permutation (a :: l2) (a :: l1)
+ | permutation_swap :
+ forall (a b : A) (l : list A), permutation (a :: b :: l) (b :: a :: l)
+ | permutation_trans :
+ forall l1 l2 l3 : list A,
+ permutation l1 l2 -> permutation l2 l3 -> permutation l1 l3.
+Hint Constructors permutation.
+
+(**************************************
+ Reflexivity
+ **************************************)
+
+Theorem permutation_refl : forall l : list A, permutation l l.
+simple induction l.
+apply permutation_nil.
+intros a l1 H.
+apply permutation_skip with (1 := H).
+Qed.
+Hint Resolve permutation_refl.
+
+(**************************************
+ Symmetry
+ **************************************)
+
+Theorem permutation_sym :
+ forall l m : list A, permutation l m -> permutation m l.
+intros l1 l2 H'; elim H'.
+apply permutation_nil.
+intros a l1' l2' H1 H2.
+apply permutation_skip with (1 := H2).
+intros a b l1'.
+apply permutation_swap.
+intros l1' l2' l3' H1 H2 H3 H4.
+apply permutation_trans with (1 := H4) (2 := H2).
+Qed.
+
+(**************************************
+ Compatibility with list length
+ **************************************)
+
+Theorem permutation_length :
+ forall l m : list A, permutation l m -> length l = length m.
+intros l m H'; elim H'; simpl in |- *; auto.
+intros l1 l2 l3 H'0 H'1 H'2 H'3.
+rewrite <- H'3; auto.
+Qed.
+
+(**************************************
+ A permutation of the nil list is the nil list
+ **************************************)
+
+Theorem permutation_nil_inv : forall l : list A, permutation l nil -> l = nil.
+intros l H; generalize (permutation_length _ _ H); case l; simpl in |- *;
+ auto.
+intros; discriminate.
+Qed.
+
+(**************************************
+ A permutation of the singleton list is the singleton list
+ **************************************)
+
+Let permutation_one_inv_aux :
+ forall l1 l2 : list A,
+ permutation l1 l2 -> forall a : A, l1 = a :: nil -> l2 = a :: nil.
+intros l1 l2 H; elim H; clear H l1 l2; auto.
+intros a l3 l4 H0 H1 b H2.
+injection H2; intros; subst; auto.
+rewrite (permutation_nil_inv _ (permutation_sym _ _ H0)); auto.
+intros; discriminate.
+Qed.
+
+Theorem permutation_one_inv :
+ forall (a : A) (l : list A), permutation (a :: nil) l -> l = a :: nil.
+intros a l H; apply permutation_one_inv_aux with (l1 := a :: nil); auto.
+Qed.
+
+(**************************************
+ Compatibility with the belonging
+ **************************************)
+
+Theorem permutation_in :
+ forall (a : A) (l m : list A), permutation l m -> In a l -> In a m.
+intros a l m H; elim H; simpl in |- *; auto; intuition.
+Qed.
+
+(**************************************
+ Compatibility with the append function
+ **************************************)
+
+Theorem permutation_app_comp :
+ forall l1 l2 l3 l4,
+ permutation l1 l2 -> permutation l3 l4 -> permutation (l1 ++ l3) (l2 ++ l4).
+intros l1 l2 l3 l4 H1; generalize l3 l4; elim H1; clear H1 l1 l2 l3 l4;
+ simpl in |- *; auto.
+intros a b l l3 l4 H.
+cut (permutation (l ++ l3) (l ++ l4)); auto.
+intros; apply permutation_trans with (a :: b :: l ++ l4); auto.
+elim l; simpl in |- *; auto.
+intros l1 l2 l3 H H0 H1 H2 l4 l5 H3.
+apply permutation_trans with (l2 ++ l4); auto.
+Qed.
+Hint Resolve permutation_app_comp.
+
+(**************************************
+ Swap two sublists
+ **************************************)
+
+Theorem permutation_app_swap :
+ forall l1 l2, permutation (l1 ++ l2) (l2 ++ l1).
+intros l1; elim l1; auto.
+intros; rewrite <- app_nil_end; auto.
+intros a l H l2.
+replace (l2 ++ a :: l) with ((l2 ++ a :: nil) ++ l).
+apply permutation_trans with (l ++ l2 ++ a :: nil); auto.
+apply permutation_trans with (((a :: nil) ++ l2) ++ l); auto.
+simpl in |- *; auto.
+apply permutation_trans with (l ++ (a :: nil) ++ l2); auto.
+apply permutation_sym; auto.
+replace (l2 ++ a :: l) with ((l2 ++ a :: nil) ++ l).
+apply permutation_app_comp; auto.
+elim l2; simpl in |- *; auto.
+intros a0 l0 H0.
+apply permutation_trans with (a0 :: a :: l0); auto.
+apply (app_ass l2 (a :: nil) l).
+apply (app_ass l2 (a :: nil) l).
+Qed.
+
+(**************************************
+ A transposition is a permutation
+ **************************************)
+
+Theorem permutation_transposition :
+ forall a b l1 l2 l3,
+ permutation (l1 ++ a :: l2 ++ b :: l3) (l1 ++ b :: l2 ++ a :: l3).
+intros a b l1 l2 l3.
+apply permutation_app_comp; auto.
+change
+ (permutation ((a :: nil) ++ l2 ++ (b :: nil) ++ l3)
+ ((b :: nil) ++ l2 ++ (a :: nil) ++ l3)) in |- *.
+repeat rewrite <- app_ass.
+apply permutation_app_comp; auto.
+apply permutation_trans with ((b :: nil) ++ (a :: nil) ++ l2); auto.
+apply permutation_app_swap; auto.
+repeat rewrite app_ass.
+apply permutation_app_comp; auto.
+apply permutation_app_swap; auto.
+Qed.
+
+(**************************************
+ An element of a list can be put on top of the list to get a permutation
+ **************************************)
+
+Theorem in_permutation_ex :
+ forall a l, In a l -> exists l1 : list A, permutation (a :: l1) l.
+intros a l; elim l; simpl in |- *; auto.
+intros H; case H; auto.
+intros a0 l0 H [H0| H0].
+exists l0; rewrite H0; auto.
+case H; auto; intros l1 Hl1; exists (a0 :: l1).
+apply permutation_trans with (a0 :: a :: l1); auto.
+Qed.
+
+(**************************************
+ A permutation of a cons can be inverted
+ **************************************)
+
+Let permutation_cons_ex_aux :
+ forall (a : A) (l1 l2 : list A),
+ permutation l1 l2 ->
+ forall l11 l12 : list A,
+ l1 = l11 ++ a :: l12 ->
+ exists l3 : list A,
+ (exists l4 : list A,
+ l2 = l3 ++ a :: l4 /\ permutation (l11 ++ l12) (l3 ++ l4)).
+intros a l1 l2 H; elim H; clear H l1 l2.
+intros l11 l12; case l11; simpl in |- *; intros; discriminate.
+intros a0 l1 l2 H H0 l11 l12; case l11; simpl in |- *.
+exists (nil (A:=A)); exists l1; simpl in |- *; split; auto.
+injection H1; intros; subst; auto.
+injection H1; intros H2 H3; rewrite <- H2; auto.
+intros a1 l111 H1.
+case (H0 l111 l12); auto.
+injection H1; auto.
+intros l3 (l4, (Hl1, Hl2)).
+exists (a0 :: l3); exists l4; split; simpl in |- *; auto.
+injection H1; intros; subst; auto.
+injection H1; intros H2 H3; rewrite H3; auto.
+intros a0 b l l11 l12; case l11; simpl in |- *.
+case l12; try (intros; discriminate).
+intros a1 l0 H; exists (b :: nil); exists l0; simpl in |- *; split; auto.
+injection H; intros; subst; auto.
+injection H; intros H1 H2 H3; rewrite H2; auto.
+intros a1 l111; case l111; simpl in |- *.
+intros H; exists (nil (A:=A)); exists (a0 :: l12); simpl in |- *; split; auto.
+injection H; intros; subst; auto.
+injection H; intros H1 H2 H3; rewrite H3; auto.
+intros a2 H1111 H; exists (a2 :: a1 :: H1111); exists l12; simpl in |- *;
+ split; auto.
+injection H; intros; subst; auto.
+intros l1 l2 l3 H H0 H1 H2 l11 l12 H3.
+case H0 with (1 := H3).
+intros l4 (l5, (Hl1, Hl2)).
+case H2 with (1 := Hl1).
+intros l6 (l7, (Hl3, Hl4)).
+exists l6; exists l7; split; auto.
+apply permutation_trans with (1 := Hl2); auto.
+Qed.
+
+Theorem permutation_cons_ex :
+ forall (a : A) (l1 l2 : list A),
+ permutation (a :: l1) l2 ->
+ exists l3 : list A,
+ (exists l4 : list A, l2 = l3 ++ a :: l4 /\ permutation l1 (l3 ++ l4)).
+intros a l1 l2 H.
+apply (permutation_cons_ex_aux a (a :: l1) l2 H nil l1); simpl in |- *; auto.
+Qed.
+
+(**************************************
+ A permutation can be simply inverted if the two list starts with a cons
+ **************************************)
+
+Theorem permutation_inv :
+ forall (a : A) (l1 l2 : list A),
+ permutation (a :: l1) (a :: l2) -> permutation l1 l2.
+intros a l1 l2 H; case permutation_cons_ex with (1 := H).
+intros l3 (l4, (Hl1, Hl2)).
+apply permutation_trans with (1 := Hl2).
+generalize Hl1; case l3; simpl in |- *; auto.
+intros H1; injection H1; intros H2; rewrite H2; auto.
+intros a0 l5 H1; injection H1; intros H2 H3; rewrite H2; rewrite H3; auto.
+apply permutation_trans with (a0 :: l4 ++ l5); auto.
+apply permutation_skip; apply permutation_app_swap.
+apply (permutation_app_swap (a0 :: l4) l5).
+Qed.
+
+(**************************************
+ Take a list and return tle list of all pairs of an element of the
+ list and the remaining list
+ **************************************)
+
+Fixpoint split_one (l : list A) : list (A * list A) :=
+ match l with
+ | nil => nil (A:=A * list A)
+ | a :: l1 =>
+ (a, l1)
+ :: map (fun p : A * list A => (fst p, a :: snd p)) (split_one l1)
+ end.
+
+(**************************************
+ The pairs of the list are a permutation
+ **************************************)
+
+Theorem split_one_permutation :
+ forall (a : A) (l1 l2 : list A),
+ In (a, l1) (split_one l2) -> permutation (a :: l1) l2.
+intros a l1 l2; generalize a l1; elim l2; clear a l1 l2; simpl in |- *; auto.
+intros a l1 H1; case H1.
+intros a l H a0 l1 [H0| H0].
+injection H0; intros H1 H2; rewrite H2; rewrite H1; auto.
+generalize H H0; elim (split_one l); simpl in |- *; auto.
+intros H1 H2; case H2.
+intros a1 l0 H1 H2 [H3| H3]; auto.
+injection H3; intros H4 H5; (rewrite <- H4; rewrite <- H5).
+apply permutation_trans with (a :: fst a1 :: snd a1); auto.
+apply permutation_skip.
+apply H2; auto.
+case a1; simpl in |- *; auto.
+Qed.
+
+(**************************************
+ All elements of the list are there
+ **************************************)
+
+Theorem split_one_in_ex :
+ forall (a : A) (l1 : list A),
+ In a l1 -> exists l2 : list A, In (a, l2) (split_one l1).
+intros a l1; elim l1; simpl in |- *; auto.
+intros H; case H.
+intros a0 l H [H0| H0]; auto.
+exists l; left; subst; auto.
+case H; auto.
+intros x H1; exists (a0 :: x); right; auto.
+apply
+ (in_map (fun p : A * list A => (fst p, a0 :: snd p)) (split_one l) (a, x));
+ auto.
+Qed.
+
+(**************************************
+ An auxillary function to generate all permutations
+ **************************************)
+
+Fixpoint all_permutations_aux (l : list A) (n : nat) {struct n} :
+ list (list A) :=
+ match n with
+ | O => nil :: nil
+ | S n1 =>
+ flat_map
+ (fun p : A * list A =>
+ map (cons (fst p)) (all_permutations_aux (snd p) n1)) (
+ split_one l)
+ end.
+(**************************************
+ Generate all the permutations
+ **************************************)
+
+Definition all_permutations (l : list A) := all_permutations_aux l (length l).
+
+(**************************************
+ All the elements of the list are permutations
+ **************************************)
+
+Let all_permutations_aux_permutation :
+ forall (n : nat) (l1 l2 : list A),
+ n = length l2 -> In l1 (all_permutations_aux l2 n) -> permutation l1 l2.
+intros n; elim n; simpl in |- *; auto.
+intros l1 l2; case l2.
+simpl in |- *; intros H0 [H1| H1].
+rewrite <- H1; auto.
+case H1.
+simpl in |- *; intros; discriminate.
+intros n0 H l1 l2 H0 H1.
+case in_flat_map_ex with (1 := H1).
+clear H1; intros x; case x; clear x; intros a1 l3 (H1, H2).
+case in_map_inv with (1 := H2).
+simpl in |- *; intros y (H3, H4).
+rewrite H4; auto.
+apply permutation_trans with (a1 :: l3); auto.
+apply permutation_skip; auto.
+apply H with (2 := H3).
+apply eq_add_S.
+apply trans_equal with (1 := H0).
+change (length l2 = length (a1 :: l3)) in |- *.
+apply permutation_length; auto.
+apply permutation_sym; apply split_one_permutation; auto.
+apply split_one_permutation; auto.
+Qed.
+
+Theorem all_permutations_permutation :
+ forall l1 l2 : list A, In l1 (all_permutations l2) -> permutation l1 l2.
+intros l1 l2 H; apply all_permutations_aux_permutation with (n := length l2);
+ auto.
+Qed.
+
+(**************************************
+ A permutation is in the list
+ **************************************)
+
+Let permutation_all_permutations_aux :
+ forall (n : nat) (l1 l2 : list A),
+ n = length l2 -> permutation l1 l2 -> In l1 (all_permutations_aux l2 n).
+intros n; elim n; simpl in |- *; auto.
+intros l1 l2; case l2.
+intros H H0; rewrite permutation_nil_inv with (1 := H0); auto with datatypes.
+simpl in |- *; intros; discriminate.
+intros n0 H l1; case l1.
+intros l2 H0 H1;
+ rewrite permutation_nil_inv with (1 := permutation_sym _ _ H1) in H0;
+ discriminate.
+clear l1; intros a1 l1 l2 H1 H2.
+case (split_one_in_ex a1 l2); auto.
+apply permutation_in with (1 := H2); auto with datatypes.
+intros x H0.
+apply in_flat_map with (b := (a1, x)); auto.
+apply in_map; simpl in |- *.
+apply H; auto.
+apply eq_add_S.
+apply trans_equal with (1 := H1).
+change (length l2 = length (a1 :: x)) in |- *.
+apply permutation_length; auto.
+apply permutation_sym; apply split_one_permutation; auto.
+apply permutation_inv with (a := a1).
+apply permutation_trans with (1 := H2).
+apply permutation_sym; apply split_one_permutation; auto.
+Qed.
+
+Theorem permutation_all_permutations :
+ forall l1 l2 : list A, permutation l1 l2 -> In l1 (all_permutations l2).
+intros l1 l2 H; unfold all_permutations in |- *;
+ apply permutation_all_permutations_aux; auto.
+Qed.
+
+(**************************************
+ Permutation is decidable
+ **************************************)
+
+Definition permutation_dec :
+ (forall a b : A, {a = b} + {a <> b}) ->
+ forall l1 l2 : list A, {permutation l1 l2} + {~ permutation l1 l2}.
+intros H l1 l2.
+case (In_dec (list_eq_dec H) l1 (all_permutations l2)).
+intros i; left; apply all_permutations_permutation; auto.
+intros i; right; contradict i; apply permutation_all_permutations; auto.
+Defined.
+
+End permutation.
+
+(**************************************
+ Hints
+ **************************************)
+
+Hint Constructors permutation.
+Hint Resolve permutation_refl.
+Hint Resolve permutation_app_comp.
+Hint Resolve permutation_app_swap.
+
+(**************************************
+ Implicits
+ **************************************)
+
+Implicit Arguments permutation [A].
+Implicit Arguments split_one [A].
+Implicit Arguments all_permutations [A].
+Implicit Arguments permutation_dec [A].
+
+(**************************************
+ Permutation is compatible with map
+ **************************************)
+
+Theorem permutation_map :
+ forall (A B : Set) (f : A -> B) l1 l2,
+ permutation l1 l2 -> permutation (map f l1) (map f l2).
+intros A B f l1 l2 H; elim H; simpl in |- *; auto.
+intros l0 l3 l4 H0 H1 H2 H3; apply permutation_trans with (2 := H3); auto.
+Qed.
+Hint Resolve permutation_map.
+
+(**************************************
+ Permutation of a map can be inverted
+ *************************************)
+
+Let permutation_map_ex_aux :
+ forall (A B : Set) (f : A -> B) l1 l2 l3,
+ permutation l1 l2 ->
+ l1 = map f l3 -> exists l4, permutation l4 l3 /\ l2 = map f l4.
+intros A1 B1 f l1 l2 l3 H; generalize l3; elim H; clear H l1 l2 l3.
+intros l3; case l3; simpl in |- *; auto.
+intros H; exists (nil (A:=A1)); auto.
+intros; discriminate.
+intros a0 l1 l2 H H0 l3; case l3; simpl in |- *; auto.
+intros; discriminate.
+intros a1 l H1; case (H0 l); auto.
+injection H1; auto.
+intros l5 (H2, H3); exists (a1 :: l5); split; simpl in |- *; auto.
+injection H1; intros; subst; auto.
+intros a0 b l l3; case l3.
+intros; discriminate.
+intros a1 l0; case l0; simpl in |- *.
+intros; discriminate.
+intros a2 l1 H; exists (a2 :: a1 :: l1); split; simpl in |- *; auto.
+injection H; intros; subst; auto.
+intros l1 l2 l3 H H0 H1 H2 l0 H3.
+case H0 with (1 := H3); auto.
+intros l4 (HH1, HH2).
+case H2 with (1 := HH2); auto.
+intros l5 (HH3, HH4); exists l5; split; auto.
+apply permutation_trans with (1 := HH3); auto.
+Qed.
+
+Theorem permutation_map_ex :
+ forall (A B : Set) (f : A -> B) l1 l2,
+ permutation (map f l1) l2 ->
+ exists l3, permutation l3 l1 /\ l2 = map f l3.
+intros A0 B f l1 l2 H; apply permutation_map_ex_aux with (l1 := map f l1);
+ auto.
+Qed.
+
+(**************************************
+ Permutation is compatible with flat_map
+ **************************************)
+
+Theorem permutation_flat_map :
+ forall (A B : Set) (f : A -> list B) l1 l2,
+ permutation l1 l2 -> permutation (flat_map f l1) (flat_map f l2).
+intros A B f l1 l2 H; elim H; simpl in |- *; auto.
+intros a b l; auto.
+repeat rewrite <- app_ass.
+apply permutation_app_comp; auto.
+intros k3 l4 l5 H0 H1 H2 H3; apply permutation_trans with (1 := H1); auto.
+Qed.