计蒜客 god of gambler

赌徒输光问题

链接：https://blog.youkuaiyun.com/xiazeyu513/article/details/78151388

#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,m;
    while(2==scanf("%d%d",&n,&m)){
        printf("%.5lf\n",1.0*n/(n+m));
    }
    return 0;
}