```
#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
int r , s;
scanf("%d%d", &r, &s);
printf("%d\n" , 2 * s - r);
return 0;
}
```
不用那么复杂
by Pikacu @ 2022-09-29 18:38:42
@[GorgeNotFound](/user/688847) 直接推公式就可以其实。。。
没必要那么麻烦用循环
by ____someone____ @ 2022-11-13 18:40:02
@[____someone____](/user/658085) 谢谢
by GorgeNotFound @ 2022-11-15 21:57:01
@[GorgeNotFound](/user/688847) 公式：S=（r1+r2)/2; S*2=r1+r2; S*2-r1=r2;
by Vuglar_zuo @ 2022-12-13 17:47:16