diff --git a/projet.use b/projet.use
index a40ba48..8f3ed2b 100644
--- a/projet.use
+++ b/projet.use
@@ -63,10 +63,8 @@ operations
     changerEtat(nouveauEtat: TypeCase)  
     getEtat(): TypeCase
 constraints
-    inv:
-        plateau.cases->select(c: Case | c.x = x and c.y = y)->size() = 1
-    inv coordonne: 
-        x <= 10 and x > 0 and y > 0 and y <= 10
+    inv: plateau.cases->select(c: Case | c.x = x and c.y = y)->size() = 1
+    inv: x <= 10 and x > 0 and y > 0 and y <= 10
 end
 
 class Bateau
@@ -75,12 +73,10 @@ attributes
     longueur: Integer
     Etat: EtatBateau
 constraints
-    inv longueur:
-        if type = TypeBateau::Torpilleur then longueur = 2
-        else if type = TypeBateau::Contre_Torpilleur then longueur = 3
-        else if type = TypeBateau::Croiseur then longueur = 4
-        else longueur = 5
-        endif endif endif
+    inv: type = TypeBateau::Torpilleur implies longueur = 2
+    inv: type = TypeBateau::Contre_Torpilleur implies longueur = 3
+    inv: type = TypeBateau::Croiseur implies longueur = 4
+    inv: type = TypeBateau::Porte_Avions implies longueur = 5
 end
 
 association Utilise between