lightoj1050

CODE

#include <iostream>

using namespace std;
int ncase;
double dp[505][505];
int main()
{
        for(int i=1;i<=500;i++)
                for(int j=1;j<=500;j++)
        {
                dp[0][j]=1;
                dp[i][j]=(1.0*i/(i+j))*dp[i-1][j-1]+(1.0*j/(i+j))*dp[i][j-2];
        }
        int t;
        cin >> t;
        while(t--)
        {
                int R,B;
                cin >> R >> B;
                cout <<"Case "<<++ncase<<": "<<dp[R][B]<<endl;
        }
        return 0;
}