Code

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int n;
        double k,t=0;
        cin>>n>>k;
        for(int i=1;i<=n;i++)
        {
            double p=t;
            t=max(t,k+t/i);
            if(p==t)i=n;
        }
        printf("%.1lf\n",t);
    }
    return 0;
}
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