#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
int t;
cin >> t;
while(t--){
int a, b;
cin >> a >> b;
if(a*a*b%(1+a) > 0)
cout << a*a*b/(1+a) + 1 << endl;
else cout << a*a*b/(1+a) << endl;
}
}
I2luY2x1ZGUgPGJpdHMvc3RkYysrLmg+CnVzaW5nIG5hbWVzcGFjZSBzdGQ7CiNkZWZpbmUgaW50IGxvbmcgbG9uZwpzaWduZWQgbWFpbigpewoJaW50IHQ7CgljaW4gPj4gdDsKCXdoaWxlKHQtLSl7CgkJaW50IGEsIGI7CgkJY2luID4+IGEgPj4gYjsKCQlpZihhKmEqYiUoMSthKSA+IDApCgkJCWNvdXQgPDwgYSphKmIvKDErYSkgKyAxIDw8IGVuZGw7CgkJZWxzZSBjb3V0IDw8IGEqYSpiLygxK2EpIDw8IGVuZGw7CgkJCQoJfQoJCn0=