save project

snake.py

@@ -52,13 +52,14 @@ while True:
         y -= 30
     else:
         y += 30
+    position.append((x, y))
     if x == xx and y == yy:
         apple_x = random.randint(1,22)
         apple_y = random.randint(1,16)
         xx,yy = apple_x*30,apple_y*30
-        screen.blit(body,position[i])
+    else:
+        position.pop(0)
     position.append((x, y))
-    position.pop(0)
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去