save project

snake.py

@@ -55,9 +55,12 @@ while True:
         y += 30
     position.append((x, y))
     if x  == xa and y == ya:
-        xa =random.randint(0,660)
-        ya =random.randint(0,480)
-    position.pop(0)
+        n1 =random.randint(0,21)
+        n2 =random.randint(0,15)
+        xa = n1 * 30
+        ya = n2 * 30
+    else:
+        position.pop(0)
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去