save project

snake.py

@@ -55,7 +55,7 @@ while True:
     position.append((x, y))
     position.pop(0)
     # 将背景图画上去
-    if  a_x ==x and a_y ==y:
+    while  a_x ==x and a_y ==y:
        a_x=random.randint(0,660)
        a_y=random.randint(0,480) 
     screen.blit(background, (0, 0))