能举反例更好
by 天下第一！ @ 2017-09-16 15:15:16
sum没开long long
by 142857cs @ 2017-09-16 16:09:58
sum应定义为long long
by _迎泽湖水怪怪 @ 2017-09-23 00:21:11
int 型装不下
by as2393125 @ 2017-10-01 21:37:15