#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define X first
#define Y second
#define pb push_back
#define SZ(a) ((int)a.size())
#define ALL(v) v.begin(), v.end()

ll f(ll n, int m) {
    for (ll x = n + 1; ; ++x) {
        if (gcd(n, x) == 1) {
            if (--m == 0) return x;        
        }
    }
}

ll solve() {
    ll k;
    int m;
    cin >> k >> m;
    vector<ll> v;
    for (ll d = 0; d <= 2000; ++d) {
        if (k == d) continue;
        v.push_back(k ^ d);
    }
    sort(v.begin(), v.end());
    for (ll n : v) {
        if (((f(n, m) - n) ^ n) == k) return n;
    }
    return -1;
}
int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int T;
    cin >> T;
    while (T--) cout << solve() << '\n';
}