#include <bits/stdc++.h>
#define _overload3(_1, _2, _3, name, ...) name
#define _rep(i, n) repi(i, 0, n)
#define repi(i, a, b) for (int i = (a); i < (b); ++i)
#define rep(...) _overload3(__VA_ARGS__, repi, _rep, )(__VA_ARGS__)
#define ALL(x) x.begin(), x.end()
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
using namespace std;
random_device rnd;
mt19937 mt(rnd());
using ll = long long;
using lld = long double;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;
using PII = pair<int, int>;
const int IINF = 1 << 30;
const ll INF = 1ll << 60;

ll frac(int n, int m)
{
    if (n == 0)
        return 1;
    return (frac(n - 1, m) * n) % m;
    ;
}

vector<bool> make_prime()
{
    vector<bool> isPrime(5 * 1010101, true);

    isPrime[0] = false;
    isPrime[1] = false;

    rep(i, 2, 5 * 1010101)
    {
        if (isPrime[i] == false)
        {
            continue;
        }
        for (int j = i + i; j < 5 * 1010101; j += i)
        {
            isPrime[j] = false;
        }
    }
    return isPrime;
}

ll mpow(ll base, ll num, ll mod)
{
    if (num == 0)
        return 1;
    ll prev = mpow(base, num / 2, mod);
    if (num % 2 == 0)
    {
        return (prev * prev) % mod;
    }
    else
    {
        return (((prev * prev) % mod) * base) % mod;
    }
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    auto isPrime = make_prime();
    int t;
    cin >> t;
    rep(i, t)
    {
        ll a, p;
        cin >> a >> p;
        if (isPrime[p])
        {
            if (a % p == 0)
            {
                cout << 0 << "\n";
            }
            else
            {
                cout << 1 << "\n";
            }
        }
        else
        {
            cout << -1 << "\n";
        }
    }
    return 0;
}