kmp: proof completed

examples/programs/kmp.mlw

@@ -103,7 +103,7 @@ module KnuthMorrisPratt
       let i = ref 1 in
       let j = ref 0 in
       while !i < m - 1 do
-        invariant { 0 <= !j <= m  /\ !j < !i <= m
+        invariant { 0 <= !j < !i <= m
          /\ matches p (!i - !j) p 0 !j
          /\ (forall z:int. !j+1 < z < !i+1 -> not matches p (!i + 1 - z) p 0 z)
          /\ (forall k:int. 0 < k <= !i -> is_next p k next[k]) }

examples/programs/kmp/kmp_WP_KnuthMorrisPratt_WP_parameter_initnext_2.v

+(* This file is generated by Why3's Coq driver *)
+(* Beware! Only edit allowed sections below    *)
+Require Import ZArith.
+Require Import Rbase.
+Definition unit  := unit.
+
+Parameter mark : Type.
+
+Parameter at1: forall (a:Type), a -> mark  -> a.
+
+Implicit Arguments at1.
+
+Parameter old: forall (a:Type), a  -> a.
+
+Implicit Arguments old.
+
+Inductive ref (a:Type) :=
+  | mk_ref : a -> ref a.
+Implicit Arguments mk_ref.
+
+Definition contents (a:Type)(u:(ref a)): a :=
+  match u with
+  | mk_ref contents1 => contents1
+  end.
+Implicit Arguments contents.
+
+Parameter map : forall (a:Type) (b:Type), Type.
+
+Parameter get: forall (a:Type) (b:Type), (map a b) -> a  -> b.
+
+Implicit Arguments get.
+
+Parameter set: forall (a:Type) (b:Type), (map a b) -> a -> b  -> (map a b).
+
+Implicit Arguments set.
+
+Axiom Select_eq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (a1 = a2) -> ((get (set m a1 b1)
+  a2) = b1).
+
+Axiom Select_neq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (~ (a1 = a2)) -> ((get (set m a1 b1)
+  a2) = (get m a2)).
+
+Parameter const: forall (b:Type) (a:Type), b  -> (map a b).
+
+Set Contextual Implicit.
+Implicit Arguments const.
+Unset Contextual Implicit.
+
+Axiom Const : forall (b:Type) (a:Type), forall (b1:b) (a1:a), ((get (const(
+  b1):(map a b)) a1) = b1).
+
+Inductive array (a:Type) :=
+  | mk_array : Z -> (map Z a) -> array a.
+Implicit Arguments mk_array.
+
+Definition elts (a:Type)(u:(array a)): (map Z a) :=
+  match u with
+  | mk_array _ elts1 => elts1
+  end.
+Implicit Arguments elts.
+
+Definition length (a:Type)(u:(array a)): Z :=
+  match u with
+  | mk_array length1 _ => length1
+  end.
+Implicit Arguments length.
+
+Definition get1 (a:Type)(a1:(array a)) (i:Z): a := (get (elts a1) i).
+Implicit Arguments get1.
+
+Definition set1 (a:Type)(a1:(array a)) (i:Z) (v:a): (array a) :=
+  match a1 with
+  | mk_array xcl0 _ => (mk_array xcl0 (set (elts a1) i v))
+  end.
+Implicit Arguments set1.
+
+Parameter char : Type.
+
+Definition matches(a1:(array char)) (i1:Z) (a2:(array char)) (i2:Z)
+  (n:Z): Prop := ((0%Z <= i1)%Z /\ (i1 <= ((length a1) - n)%Z)%Z) /\
+  (((0%Z <= i2)%Z /\ (i2 <= ((length a2) - n)%Z)%Z) /\ forall (i:Z),
+  ((0%Z <= i)%Z /\ (i <  n)%Z) -> ((get1 a1 (i1 + i)%Z) = (get1 a2
+  (i2 + i)%Z))).
+
+Axiom matches_empty : forall (a1:(array char)) (a2:(array char)) (i1:Z)
+  (i2:Z), ((0%Z <= i1)%Z /\ (i1 <= (length a1))%Z) -> (((0%Z <= i2)%Z /\
+  (i2 <= (length a2))%Z) -> (matches a1 i1 a2 i2 0%Z)).
+
+Axiom matches_right_extension : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z), (matches a1 i1 a2 i2 n) ->
+  ((i1 <= (((length a1) - n)%Z - 1%Z)%Z)%Z ->
+  ((i2 <= (((length a2) - n)%Z - 1%Z)%Z)%Z -> (((get1 a1
+  (i1 + n)%Z) = (get1 a2 (i2 + n)%Z)) -> (matches a1 i1 a2 i2
+  (n + 1%Z)%Z)))).
+
+Axiom matches_contradiction_at_first : forall (a1:(array char)) (a2:(array
+  char)) (i1:Z) (i2:Z) (n:Z), (0%Z <  n)%Z -> ((~ ((get1 a1 i1) = (get1 a2
+  i2))) -> ~ (matches a1 i1 a2 i2 n)).
+
+Axiom matches_contradiction_at_i : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (i:Z) (n:Z), (0%Z <  n)%Z -> (((0%Z <= i)%Z /\ (i <  n)%Z) ->
+  ((~ ((get1 a1 (i1 + i)%Z) = (get1 a2 (i2 + i)%Z))) -> ~ (matches a1 i1 a2
+  i2 n))).
+
+Axiom matches_right_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 i1 a2 i2 n) -> ((nqt <  n)%Z ->
+  (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_left_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 (i1 - (n - nqt)%Z)%Z a2
+  (i2 - (n - nqt)%Z)%Z n) -> ((nqt <  n)%Z -> (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_sym : forall (a1:(array char)) (a2:(array char)) (i1:Z) (i2:Z)
+  (n:Z), (matches a1 i1 a2 i2 n) -> (matches a2 i2 a1 i1 n).
+
+Axiom matches_trans : forall (a1:(array char)) (a2:(array char)) (a3:(array
+  char)) (i1:Z) (i2:Z) (i3:Z) (n:Z), (matches a1 i1 a2 i2 n) -> ((matches a2
+  i2 a3 i3 n) -> (matches a1 i1 a3 i3 n)).
+
+Definition is_next(p:(array char)) (j:Z) (n:Z): Prop := ((0%Z <= n)%Z /\
+  (n <  j)%Z) /\ ((matches p (j - n)%Z p 0%Z n) /\ forall (z:Z),
+  ((n <  z)%Z /\ (z <  j)%Z) -> ~ (matches p (j - z)%Z p 0%Z z)).
+
+Axiom next_iteration : forall (p:(array char)) (a:(array char)) (i:Z) (j:Z)
+  (n:Z), ((0%Z <  j)%Z /\ (j <  (length p))%Z) -> (((j <= i)%Z /\
+  (i <= (length a))%Z) -> ((matches a (i - j)%Z p 0%Z j) -> ((is_next p j
+  n) -> (matches a (i - n)%Z p 0%Z n)))).
+
+Axiom next_is_maximal : forall (p:(array char)) (a:(array char)) (i:Z) (j:Z)
+  (n:Z) (k:Z), ((0%Z <  j)%Z /\ (j <  (length p))%Z) -> (((j <= i)%Z /\
+  (i <= (length a))%Z) -> ((((i - j)%Z <  k)%Z /\ (k <  (i - n)%Z)%Z) ->
+  ((matches a (i - j)%Z p 0%Z j) -> ((is_next p j n) -> ~ (matches a k p 0%Z
+  (length p)))))).
+
+Axiom next_1_0 : forall (p:(array char)), (1%Z <= (length p))%Z -> (is_next p
+  1%Z 0%Z).
+
+Definition lt_nat(x:Z) (y:Z): Prop := (0%Z <= y)%Z /\ (x <  y)%Z.
+
+Inductive lex : (Z* Z)%type -> (Z* Z)%type -> Prop :=
+  | Lex_1 : forall (x1:Z) (x2:Z) (y1:Z) (y2:Z), (lt_nat x1 x2) -> (lex (x1,
+      y1) (x2, y2))
+  | Lex_2 : forall (x:Z) (y1:Z) (y2:Z), (lt_nat y1 y2) -> (lex (x, y1) (x,
+      y2)).
+
+Parameter p:  (array char).
+
+
+Parameter next:  (array Z).
+
+
+Theorem WP_parameter_initnext : forall (next1:Z), forall (p1:Z),
+  forall (next2:(map Z Z)), forall (p2:(map Z char)), let p3 := (mk_array p1
+  p2) in (((1%Z <= next1)%Z /\ (next1 = p1)) -> ((1%Z <  p1)%Z ->
+  (((0%Z <= 1%Z)%Z /\ (1%Z <  next1)%Z) -> forall (next3:(map Z Z)),
+  (next3 = (set next2 1%Z 0%Z)) -> forall (j:Z), forall (i:Z),
+  forall (next4:(map Z Z)), ((((0%Z <= j)%Z /\ (j <  i)%Z) /\ (i <= p1)%Z) /\
+  ((matches p3 (i - j)%Z p3 0%Z j) /\ ((forall (z:Z),
+  (((j + 1%Z)%Z <  z)%Z /\ (z <  (i + 1%Z)%Z)%Z) -> ~ (matches p3
+  ((i + 1%Z)%Z - z)%Z p3 0%Z z)) /\ forall (k:Z), ((0%Z <  k)%Z /\
+  (k <= i)%Z) -> (is_next p3 k (get next4 k))))) -> ((i <  (p1 - 1%Z)%Z)%Z ->
+  (((0%Z <= i)%Z /\ (i <  p1)%Z) -> (((0%Z <= j)%Z /\ (j <  p1)%Z) ->
+  (((get p2 i) = (get p2 j)) -> forall (i1:Z), (i1 = (i + 1%Z)%Z) ->
+  forall (j1:Z), (j1 = (j + 1%Z)%Z) -> (((0%Z <= i1)%Z /\ (i1 <  next1)%Z) ->
+  forall (next5:(map Z Z)), (next5 = (set next4 i1 j1)) -> forall (z:Z),
+  (((j1 + 1%Z)%Z <  z)%Z /\ (z <  (i1 + 1%Z)%Z)%Z) -> ~ (matches p3
+  ((i1 + 1%Z)%Z - z)%Z p3 0%Z z))))))))).
+(* YOU MAY EDIT THE PROOF BELOW *)
+intros n n1 next1 p1.
+intro p3. unfold p3. clear p3.
+intros (_, eqn). subst n1. intros hn _ _ _.
+intros j i next4 ((hj, hi), (h0, (h1, h2))).
+intros hi' _ _ eq.
+intros i1 hi1; subst i1.
+intros j1 hji1; subst j1.
+intros _ _ _ z hz.
+red; intro h. unfold matches, length , get1 in h. simpl in h.
+destruct h as (hy1, (hy2, hy3)).
+
+apply h1 with (z-1)%Z.
+omega.
+red; unfold length, get1; simpl.
+repeat split; try omega.
+intros.
+replace (i + 1 - (z - 1) + i0)%Z with (i + 1 + 1 - z + i0)%Z by omega.
+apply hy3.
+omega.
+Qed.
+(* DO NOT EDIT BELOW *)
+
+

examples/programs/kmp/kmp_WP_KnuthMorrisPratt_WP_parameter_initnext_3.v

+(* This file is generated by Why3's Coq driver *)
+(* Beware! Only edit allowed sections below    *)
+Require Import ZArith.
+Require Import Rbase.
+Definition unit  := unit.
+
+Parameter mark : Type.
+
+Parameter at1: forall (a:Type), a -> mark  -> a.
+
+Implicit Arguments at1.
+
+Parameter old: forall (a:Type), a  -> a.
+
+Implicit Arguments old.
+
+Inductive ref (a:Type) :=
+  | mk_ref : a -> ref a.
+Implicit Arguments mk_ref.
+
+Definition contents (a:Type)(u:(ref a)): a :=
+  match u with
+  | mk_ref contents1 => contents1
+  end.
+Implicit Arguments contents.
+
+Parameter map : forall (a:Type) (b:Type), Type.
+
+Parameter get: forall (a:Type) (b:Type), (map a b) -> a  -> b.
+
+Implicit Arguments get.
+
+Parameter set: forall (a:Type) (b:Type), (map a b) -> a -> b  -> (map a b).
+
+Implicit Arguments set.
+
+Axiom Select_eq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (a1 = a2) -> ((get (set m a1 b1)
+  a2) = b1).
+
+Axiom Select_neq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (~ (a1 = a2)) -> ((get (set m a1 b1)
+  a2) = (get m a2)).
+
+Parameter const: forall (b:Type) (a:Type), b  -> (map a b).
+
+Set Contextual Implicit.
+Implicit Arguments const.
+Unset Contextual Implicit.
+
+Axiom Const : forall (b:Type) (a:Type), forall (b1:b) (a1:a), ((get (const(
+  b1):(map a b)) a1) = b1).
+
+Inductive array (a:Type) :=
+  | mk_array : Z -> (map Z a) -> array a.
+Implicit Arguments mk_array.
+
+Definition elts (a:Type)(u:(array a)): (map Z a) :=
+  match u with
+  | mk_array _ elts1 => elts1
+  end.
+Implicit Arguments elts.
+
+Definition length (a:Type)(u:(array a)): Z :=
+  match u with
+  | mk_array length1 _ => length1
+  end.
+Implicit Arguments length.
+
+Definition get1 (a:Type)(a1:(array a)) (i:Z): a := (get (elts a1) i).
+Implicit Arguments get1.
+
+Definition set1 (a:Type)(a1:(array a)) (i:Z) (v:a): (array a) :=
+  match a1 with
+  | mk_array xcl0 _ => (mk_array xcl0 (set (elts a1) i v))
+  end.
+Implicit Arguments set1.
+
+Parameter char : Type.
+
+Definition matches(a1:(array char)) (i1:Z) (a2:(array char)) (i2:Z)
+  (n:Z): Prop := ((0%Z <= i1)%Z /\ (i1 <= ((length a1) - n)%Z)%Z) /\
+  (((0%Z <= i2)%Z /\ (i2 <= ((length a2) - n)%Z)%Z) /\ forall (i:Z),
+  ((0%Z <= i)%Z /\ (i <  n)%Z) -> ((get1 a1 (i1 + i)%Z) = (get1 a2
+  (i2 + i)%Z))).
+
+Axiom matches_empty : forall (a1:(array char)) (a2:(array char)) (i1:Z)
+  (i2:Z), ((0%Z <= i1)%Z /\ (i1 <= (length a1))%Z) -> (((0%Z <= i2)%Z /\
+  (i2 <= (length a2))%Z) -> (matches a1 i1 a2 i2 0%Z)).
+
+Axiom matches_right_extension : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z), (matches a1 i1 a2 i2 n) ->
+  ((i1 <= (((length a1) - n)%Z - 1%Z)%Z)%Z ->
+  ((i2 <= (((length a2) - n)%Z - 1%Z)%Z)%Z -> (((get1 a1
+  (i1 + n)%Z) = (get1 a2 (i2 + n)%Z)) -> (matches a1 i1 a2 i2
+  (n + 1%Z)%Z)))).
+
+Axiom matches_contradiction_at_first : forall (a1:(array char)) (a2:(array
+  char)) (i1:Z) (i2:Z) (n:Z), (0%Z <  n)%Z -> ((~ ((get1 a1 i1) = (get1 a2
+  i2))) -> ~ (matches a1 i1 a2 i2 n)).
+
+Axiom matches_contradiction_at_i : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (i:Z) (n:Z), (0%Z <  n)%Z -> (((0%Z <= i)%Z /\ (i <  n)%Z) ->
+  ((~ ((get1 a1 (i1 + i)%Z) = (get1 a2 (i2 + i)%Z))) -> ~ (matches a1 i1 a2
+  i2 n))).
+
+Axiom matches_right_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 i1 a2 i2 n) -> ((nqt <  n)%Z ->
+  (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_left_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 (i1 - (n - nqt)%Z)%Z a2
+  (i2 - (n - nqt)%Z)%Z n) -> ((nqt <  n)%Z -> (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_sym : forall (a1:(array char)) (a2:(array char)) (i1:Z) (i2:Z)
+  (n:Z), (matches a1 i1 a2 i2 n) -> (matches a2 i2 a1 i1 n).
+
+Axiom matches_trans : forall (a1:(array char)) (a2:(array char)) (a3:(array
+  char)) (i1:Z) (i2:Z) (i3:Z) (n:Z), (matches a1 i1 a2 i2 n) -> ((matches a2
+  i2 a3 i3 n) -> (matches a1 i1 a3 i3 n)).
+
+Definition is_next(p:(array char)) (j:Z) (n:Z): Prop := ((0%Z <= n)%Z /\
+  (n <  j)%Z) /\ ((matches p (j - n)%Z p 0%Z n) /\ forall (z:Z),
+  ((n <  z)%Z /\ (z <  j)%Z) -> ~ (matches p (j - z)%Z p 0%Z z)).
+
+Axiom next_iteration : forall (p:(array char)) (a:(array char)) (i:Z) (j:Z)
+  (n:Z), ((0%Z <  j)%Z /\ (j <  (length p))%Z) -> (((j <= i)%Z /\
+  (i <= (length a))%Z) -> ((matches a (i - j)%Z p 0%Z j) -> ((is_next p j
+  n) -> (matches a (i - n)%Z p 0%Z n)))).
+
+Axiom next_is_maximal : forall (p:(array char)) (a:(array char)) (i:Z) (j:Z)
+  (n:Z) (k:Z), ((0%Z <  j)%Z /\ (j <  (length p))%Z) -> (((j <= i)%Z /\
+  (i <= (length a))%Z) -> ((((i - j)%Z <  k)%Z /\ (k <  (i - n)%Z)%Z) ->
+  ((matches a (i - j)%Z p 0%Z j) -> ((is_next p j n) -> ~ (matches a k p 0%Z
+  (length p)))))).
+
+Axiom next_1_0 : forall (p:(array char)), (1%Z <= (length p))%Z -> (is_next p
+  1%Z 0%Z).
+
+Definition lt_nat(x:Z) (y:Z): Prop := (0%Z <= y)%Z /\ (x <  y)%Z.
+
+Inductive lex : (Z* Z)%type -> (Z* Z)%type -> Prop :=
+  | Lex_1 : forall (x1:Z) (x2:Z) (y1:Z) (y2:Z), (lt_nat x1 x2) -> (lex (x1,
+      y1) (x2, y2))
+  | Lex_2 : forall (x:Z) (y1:Z) (y2:Z), (lt_nat y1 y2) -> (lex (x, y1) (x,
+      y2)).
+
+Parameter p:  (array char).
+
+
+Parameter next:  (array Z).
+
+
+Theorem WP_parameter_initnext : forall (next1:Z), forall (p1:Z),
+  forall (next2:(map Z Z)), forall (p2:(map Z char)), let p3 := (mk_array p1
+  p2) in (((1%Z <= next1)%Z /\ (next1 = p1)) -> ((1%Z <  p1)%Z ->
+  (((0%Z <= 1%Z)%Z /\ (1%Z <  next1)%Z) -> forall (next3:(map Z Z)),
+  (next3 = (set next2 1%Z 0%Z)) -> forall (j:Z), forall (i:Z),
+  forall (next4:(map Z Z)), ((((0%Z <= j)%Z /\ (j <  i)%Z) /\ (i <= p1)%Z) /\
+  ((matches p3 (i - j)%Z p3 0%Z j) /\ ((forall (z:Z),
+  (((j + 1%Z)%Z <  z)%Z /\ (z <  (i + 1%Z)%Z)%Z) -> ~ (matches p3
+  ((i + 1%Z)%Z - z)%Z p3 0%Z z)) /\ forall (k:Z), ((0%Z <  k)%Z /\
+  (k <= i)%Z) -> (is_next p3 k (get next4 k))))) -> ((i <  (p1 - 1%Z)%Z)%Z ->
+  (((0%Z <= i)%Z /\ (i <  p1)%Z) -> (((0%Z <= j)%Z /\ (j <  p1)%Z) ->
+  ((~ ((get p2 i) = (get p2 j))) -> ((j = 0%Z) -> forall (i1:Z),
+  (i1 = (i + 1%Z)%Z) -> (((0%Z <= i1)%Z /\ (i1 <  next1)%Z) ->
+  forall (next5:(map Z Z)), (next5 = (set next4 i1 0%Z)) -> forall (z:Z),
+  (((j + 1%Z)%Z <  z)%Z /\ (z <  (i1 + 1%Z)%Z)%Z) -> ~ (matches p3
+  ((i1 + 1%Z)%Z - z)%Z p3 0%Z z)))))))))).
+(* YOU MAY EDIT THE PROOF BELOW *)
+intros n n1 next1 p1.
+intro p3. unfold p3. clear p3.
+intros (_, eqn). subst n1. intros hn _ _ _.
+intros j i next4 ((hj, hi), (h0, (h1, h2))).
+intros hi' _ _ neq j0. subst j.
+intros i1 hi1; subst i1.
+intros _ _ _ z hz.
+red; intro h. unfold matches, length , get1 in h. simpl in h.
+destruct h as (hy1, (hy2, hy3)).
+
+assert (case: (z = 2 \/ 2 < z)%Z) by omega. destruct case.
+subst z.
+absurd (get p1 i = get p1 0%Z); auto.
+generalize (hy3 0%Z).
+ring_simplify (i + 1 + 1 - 2 + 0)%Z.
+intuition.
+
+apply h1 with (z-1)%Z.
+omega.
+red; unfold length, get1; simpl.
+repeat split; try omega.
+intros.
+replace (i + 1 - (z - 1) + i0)%Z with (i + 1 + 1 - z + i0)%Z by omega.
+apply hy3.
+omega.
+Qed.
+(* DO NOT EDIT BELOW *)
+
+

examples/programs/kmp/kmp_WP_KnuthMorrisPratt_WP_parameter_initnext_4.v

+(* This file is generated by Why3's Coq driver *)
+(* Beware! Only edit allowed sections below    *)
+Require Import ZArith.
+Require Import Rbase.
+Definition unit  := unit.
+
+Parameter mark : Type.
+
+Parameter at1: forall (a:Type), a -> mark  -> a.
+
+Implicit Arguments at1.
+
+Parameter old: forall (a:Type), a  -> a.
+
+Implicit Arguments old.
+
+Inductive ref (a:Type) :=
+  | mk_ref : a -> ref a.
+Implicit Arguments mk_ref.
+
+Definition contents (a:Type)(u:(ref a)): a :=
+  match u with
+  | mk_ref contents1 => contents1
+  end.
+Implicit Arguments contents.
+
+Parameter map : forall (a:Type) (b:Type), Type.
+
+Parameter get: forall (a:Type) (b:Type), (map a b) -> a  -> b.
+
+Implicit Arguments get.
+
+Parameter set: forall (a:Type) (b:Type), (map a b) -> a -> b  -> (map a b).
+
+Implicit Arguments set.
+
+Axiom Select_eq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (a1 = a2) -> ((get (set m a1 b1)
+  a2) = b1).
+
+Axiom Select_neq : forall (a:Type) (b:Type), forall (m:(map a b)),
+  forall (a1:a) (a2:a), forall (b1:b), (~ (a1 = a2)) -> ((get (set m a1 b1)
+  a2) = (get m a2)).
+
+Parameter const: forall (b:Type) (a:Type), b  -> (map a b).
+
+Set Contextual Implicit.
+Implicit Arguments const.
+Unset Contextual Implicit.
+
+Axiom Const : forall (b:Type) (a:Type), forall (b1:b) (a1:a), ((get (const(
+  b1):(map a b)) a1) = b1).
+
+Inductive array (a:Type) :=
+  | mk_array : Z -> (map Z a) -> array a.
+Implicit Arguments mk_array.
+
+Definition elts (a:Type)(u:(array a)): (map Z a) :=
+  match u with
+  | mk_array _ elts1 => elts1
+  end.
+Implicit Arguments elts.
+
+Definition length (a:Type)(u:(array a)): Z :=
+  match u with
+  | mk_array length1 _ => length1
+  end.
+Implicit Arguments length.
+
+Definition get1 (a:Type)(a1:(array a)) (i:Z): a := (get (elts a1) i).
+Implicit Arguments get1.
+
+Definition set1 (a:Type)(a1:(array a)) (i:Z) (v:a): (array a) :=
+  match a1 with
+  | mk_array xcl0 _ => (mk_array xcl0 (set (elts a1) i v))
+  end.
+Implicit Arguments set1.
+
+Parameter char : Type.
+
+Definition matches(a1:(array char)) (i1:Z) (a2:(array char)) (i2:Z)
+  (n:Z): Prop := ((0%Z <= i1)%Z /\ (i1 <= ((length a1) - n)%Z)%Z) /\
+  (((0%Z <= i2)%Z /\ (i2 <= ((length a2) - n)%Z)%Z) /\ forall (i:Z),
+  ((0%Z <= i)%Z /\ (i <  n)%Z) -> ((get1 a1 (i1 + i)%Z) = (get1 a2
+  (i2 + i)%Z))).
+
+Axiom matches_empty : forall (a1:(array char)) (a2:(array char)) (i1:Z)
+  (i2:Z), ((0%Z <= i1)%Z /\ (i1 <= (length a1))%Z) -> (((0%Z <= i2)%Z /\
+  (i2 <= (length a2))%Z) -> (matches a1 i1 a2 i2 0%Z)).
+
+Axiom matches_right_extension : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z), (matches a1 i1 a2 i2 n) ->
+  ((i1 <= (((length a1) - n)%Z - 1%Z)%Z)%Z ->
+  ((i2 <= (((length a2) - n)%Z - 1%Z)%Z)%Z -> (((get1 a1
+  (i1 + n)%Z) = (get1 a2 (i2 + n)%Z)) -> (matches a1 i1 a2 i2
+  (n + 1%Z)%Z)))).
+
+Axiom matches_contradiction_at_first : forall (a1:(array char)) (a2:(array
+  char)) (i1:Z) (i2:Z) (n:Z), (0%Z <  n)%Z -> ((~ ((get1 a1 i1) = (get1 a2
+  i2))) -> ~ (matches a1 i1 a2 i2 n)).
+
+Axiom matches_contradiction_at_i : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (i:Z) (n:Z), (0%Z <  n)%Z -> (((0%Z <= i)%Z /\ (i <  n)%Z) ->
+  ((~ ((get1 a1 (i1 + i)%Z) = (get1 a2 (i2 + i)%Z))) -> ~ (matches a1 i1 a2
+  i2 n))).
+
+Axiom matches_right_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 i1 a2 i2 n) -> ((nqt <  n)%Z ->
+  (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_left_weakening : forall (a1:(array char)) (a2:(array char))
+  (i1:Z) (i2:Z) (n:Z) (nqt:Z), (matches a1 (i1 - (n - nqt)%Z)%Z a2
+  (i2 - (n - nqt)%Z)%Z n) -> ((nqt <  n)%Z -> (matches a1 i1 a2 i2 nqt)).
+
+Axiom matches_sym : forall (a1:(array char)) (a2:(array char)) (i1:Z) (i2:Z)
+  (n:Z), (matches a1 i1 a2 i2 n) -> (matches a2 i2 a1 i1 n).
+