save project

snake.py

@@ -69,9 +69,12 @@ while True:
         num2=random.randint(1,16)
         apple_x=num1*30-30
         apple_y=num2*30-30
-        score=+1
+        score=score+1
     else:
         position.pop(0)
+
+    if x<0 or x>630 or y<0 or y>450:
+        exit()
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去
@@ -87,4 +90,4 @@ while True:
     screen.blit(text,(540,10))
     # 刷新画面
     pygame.display.update()
-    FPSCLOCK.tick(3)
\ No newline at end of file
+    FPSCLOCK.tick(4)
\ No newline at end of file