diff --git a/du3/program.c b/du3/program.c
index cece3e6..3c9b20e 100644
--- a/du3/program.c
+++ b/du3/program.c
@@ -95,8 +95,8 @@ int main(void) {
             }
             push_stack(&s, result);
         } else {
-            printf("Chyba: neplatny vstup.\n");
-            return 1;
+            printf("bad input\n");
+            return 0;
         }
 
         print_stack(&s);