diff --git a/cv9/snake.c b/cv9/snake.c
index 3c522f6..829401e 100644
--- a/cv9/snake.c
+++ b/cv9/snake.c
@@ -35,7 +35,11 @@ struct snake* remove_snake(struct snake* snake) {
 void free_snake(struct snake* sn){
 }
 
-int is_snake(struct snake* snake,int x,int y){
+int is_snake(struct snake* snake, int x, int y) {
+    while (snake) {
+        if (snake->x == x && snake->y == y) return 1;
+        snake = snake->next;
+    }
     return 0;
 }