X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fmatita%2Flibrary%2Fnat%2Fminimization.ma;h=72812cb651ecf447983be299aa9e94d00794af64;hb=aeb7f0539398561dc84cadf38df14a051dd1ba75;hp=bb3475150092077bed0f14ff915dcf0fc0b531e8;hpb=39eee3ee34bd22321d7b80c2685395345a0957e0;p=helm.git

diff --git a/helm/matita/library/nat/minimization.ma b/helm/matita/library/nat/minimization.ma
index bb3475150..72812cb65 100644
--- a/helm/matita/library/nat/minimization.ma
+++ b/helm/matita/library/nat/minimization.ma
@@ -72,12 +72,13 @@ intro.simplify.rewrite < H3.
 rewrite > H2.simplify.apply le_n.
 qed.
 
+
 definition max_spec \def \lambda f:nat \to bool.\lambda n: nat.
-ex nat (\lambda i:nat. (le i n) \land (f i = true)) \to
+\exists i. (le i n) \land (f i = true) \to
 (f n) = true \land (\forall i. i < n \to (f i = false)).
 
 theorem f_max_true : \forall f:nat \to bool. \forall n:nat.
-ex nat (\lambda i:nat. (le i n) \land (f i = true)) \to f (max n f) = true. 
+(\exists i:nat. le i n \land f i = true) \to f (max n f) = true. 
 intros 2.
 elim n.elim H.elim H1.generalize in match H3.
 apply le_n_O_elim a H2.intro.simplify.rewrite > H4.
@@ -86,8 +87,7 @@ simplify.
 apply bool_ind (\lambda b:bool.
 (f (S n1) = b) \to (f ([\lambda b:bool.nat] match b in bool with
 [ true \Rightarrow (S n1)
-| false  \Rightarrow (max n1 f)])) = true) ? ? ?.
-reflexivity.
+| false  \Rightarrow (max n1 f)])) = true).
 simplify.intro.assumption.
 simplify.intro.apply H.
 elim H1.elim H3.generalize in match H5.
@@ -95,8 +95,9 @@ apply le_n_Sm_elim a n1 H4.
 intros.
 apply ex_intro nat ? a.
 split.apply le_S_S_to_le.assumption.assumption.
-intros.apply False_ind.apply not_eq_true_false ?.
+intros.apply False_ind.apply not_eq_true_false.
 rewrite < H2.rewrite < H7.rewrite > H6. reflexivity.
+reflexivity.
 qed.
 
 theorem lt_max_to_false : \forall f:nat \to bool. 
@@ -106,7 +107,6 @@ elim n.absurd le m O.assumption.
 cut O < m.apply lt_O_n_elim m Hcut.exact not_le_Sn_O.
 rewrite < max_O_f f.assumption.
 generalize in match H1.
-(* ?? non posso generalizzare su un goal implicativo ?? *)
 elim max_S_max f n1.
 elim H3.
 absurd m \le S n1.assumption.
@@ -152,7 +152,7 @@ simplify.right.split.reflexivity.reflexivity.
 qed.
 
 theorem f_min_aux_true: \forall f:nat \to bool. \forall off,m:nat.
-ex nat (\lambda i:nat. (le (m-off) i) \land (le i m) \land (f i = true)) \to
+(\exists i. le (m-off) i \land le i m \land f i = true) \to
 f (min_aux off m f) = true. 
 intros 2.
 elim off.elim H.elim H1.elim H2.
@@ -163,8 +163,7 @@ simplify.
 apply bool_ind (\lambda b:bool.
 (f (m-(S n)) = b) \to (f ([\lambda b:bool.nat] match b in bool with
 [ true \Rightarrow m-(S n)
-| false  \Rightarrow (min_aux n m f)])) = true) ? ? ?.
-reflexivity.
+| false  \Rightarrow (min_aux n m f)])) = true).
 simplify.intro.assumption.
 simplify.intro.apply H.
 elim H1.elim H3.elim H4.
@@ -176,6 +175,7 @@ assumption.assumption.
 absurd f a = false.rewrite < H8.assumption.
 rewrite > H5.
 apply not_eq_true_false.
+reflexivity.
 qed.
 
 theorem lt_min_aux_to_false : \forall f:nat \to bool. 
@@ -191,8 +191,9 @@ apply lt_to_not_le.rewrite < H6.assumption.
 elim H3.
 elim le_to_or_lt_eq (n -(S n1)) m.
 apply H.apply lt_minus_S_n_to_le_minus_n.assumption.
-rewrite < H6.assumption.assumption.
+rewrite < H6.assumption.
 rewrite < H7.assumption.
+assumption.
 qed.
 
 theorem le_min_aux : \forall f:nat \to bool. 
@@ -203,7 +204,7 @@ rewrite > min_aux_O_f f n.apply le_n.
 elim min_aux_S f n1 n.
 elim H1.rewrite > H3.apply le_n.
 elim H1.rewrite > H3.
-apply trans_le (n-(S n1)) (n-n1) ?.
+apply trans_le (n-(S n1)) (n-n1).
 apply monotonic_le_minus_r.
 apply le_n_Sn.
 assumption.