#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
bool b[5000010] = { false };
int main() {
	for (int i = 2; i <= 5000000; i++) {
		if (!b[i]) {
			for (int j = i + i; j <= 5000000; j += i) {
				b[j] = true;
			}
		}
	}
	int t;
	cin >> t;
	long long a, p;
	for (int i = 0; i < t; i++) {
		cin >> a >> p;
		if (b[p]) {
			cout << "-1" << endl;
		}
		else {
			if (a % p != 0 && p % a != 0) {
				cout << "1" << endl;
			}
			else {
				cout << "0" << endl;
			}
		}
	}
	return 0;
}