#include<bits/stdc++.h>
using namespace std;
#define ll long long int 
int main()
{
  ll tc;
    cin>>tc;
    while(tc--)
    {
        ll n,m;
        cin>>n>>m;
       ll l=0,r=m/n,ans=0;
        while(l<=r)
        {
            ll mid=(l+(r-l)/2);
            ll u=mid*n;
            ll d=(m-(u));
            ll g=d*mid;
            if(d>=u)
            {
                ans=max(ans,g);
                l=mid+1;
            }
            else
            {
                ans=max(ans,g);
                r=mid-1;
            }
        }
        cout<<ans<<endl;
    }
}