save project

snake.py

@@ -60,7 +60,9 @@ while True:
         apple_x=s1*30-30
         apple_x=s1*30-30
         apple_y=s2*30-30
         apple_y=s2*30-30
     else:
     else:
-        position.pop(0)            
+        position.pop(0)
+    if 650<x or 0>x or 450<y or 0>y:
+        exit()                
     position.append((x, y))
     position.append((x, y))
     # 将背景图画上去
     # 将背景图画上去
     screen.blit(background, (0, 0))
     screen.blit(background, (0, 0))