save project

snake.py

@@ -63,9 +63,12 @@ while True:
         num2 = random.randint(1,16)
         apple_x = num1*30-30
         apple_y = num2*30-30
+        score+=10
     else :
         position.pop(0)
     # 将背景图画上去
+    if x<0 or x>630 or y<0 or y>450:
+        exit()
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去
     screen.blit(snake_head, position[-1])