@[hoper007](/user/808654)
```cpp
b[pos_b]=tmp1+tmp2;
```
如果上面第一小第二小都不在b里，那么b[pos_b]会被反复赋值
by PluviaLaver @ 2023-07-02 08:40:18
@[llbear](/user/271238) 明白了AC了，感谢
by FIGFUH001 @ 2023-07-02 08:41:54