# ~~**因为你没有用Markdown**~~
by SadLava @ 2019-10-25 18:56:25
```cpp
include<iostream>
using namespace std;
int main(){
int s,r_1;
cin>>s>>r_1;
int r_2=2*s-r_1;
cout<<r_2<<endl;
return 0;
}
```
~~帮忙整理一下~~
by B_lhx @ 2019-10-25 19:03:42
@[这人特别菜](/space/show?uid=273124)
应该是
```cpp
include<iostream>
using namespace std;
int main(){
int s,r_1;
cin>>s>>r_1;
int r_2=2*r_1-s;
cout<<r_2<<endl;
return 0;
}
```
by 已注销ZdCpmQy3 @ 2019-10-25 19:08:38
谢谢各位大佬
by 这人特别菜 @ 2019-10-26 18:01:15