#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int T;
    cin >> T;
    while(T--){
        ll n, m;
        cin >> n >> m;
        ll ok = 0, ng = 1ll << 40;
        while(ok + 1 < ng){
            ll mid = (ok + ng) / 2;
            ll d = (mid + 2) / 3;
            ll B = max(0ll, d * 2 - m);
            while(B % 4 != 0) B++;
            ll W = B / 2 + d * 4;
            (n >= W ? ok : ng) = mid;
        }
        cout << ok << '\n';
    }
}