diff --git a/du5/snake.c b/du5/snake.c
index 95ef638..802286d 100644
--- a/du5/snake.c
+++ b/du5/snake.c
@@ -45,7 +45,7 @@ struct snake* remove_snake(struct snake* snake) {
 int is_snake(struct snake* snake, int x, int y) {
     struct snake* current = snake;
 
-    while () {
+    while (current !=NULL) {
         if ((current->x==x) && (current->y==y)) {
             return 1;
         }
diff --git a/du5/snake.o b/du5/snake.o
index 49ce4f7..cf3be55 100644
Binary files a/du5/snake.o and b/du5/snake.o differ