https://www.luogu.org/problemnew/solution/P2727
by ♘GoldHookDream♞ @ 2019-08-21 16:16:22
...
by dfydada⚡⚡⚡ @ 2019-08-21 18:37:58
判断2进制数中有几个一：
```
int sum(long long x){
int cnt=0;
while(x){
x&=x-1;
cnt++;
}
return cnt;
}
```
by george0929 @ 2023-05-20 08:41:04