diff --git a/dm5/lib/lib.ml b/dm5/lib/lib.ml
index 1f72dc6..f438994 100644
--- a/dm5/lib/lib.ml
+++ b/dm5/lib/lib.ml
@@ -27,7 +27,7 @@ let croissant t =
   while !i+1 < n && t.(!i) <= t.(!i+1) do
     i := !i+1
   done;
-  !i
+  !i = (n-1)
 ;;
 
 (* Exercice 4 *)