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

int main()
{
	int t;
	cin >> t;
	vector<int> prime(5*1000000+1,1);
	for(int i = 2;i<5*1000000+1;i++)
	{
		if(prime[i])
		{
			for(int j = i*2;j<5*1000000+1;j+=i)
			{
				prime[j] = false;
			}
		}
	}
	prime[0] = prime[1] = false;
	while(t--)
	{
		int a,p;
		cin >> a >> p;
		if(prime[p])
		{
			if(a%p==0)
			{
				cout<<0<<endl;
			}
			else cout << 1 << endl;
		}
		else cout << -1 << endl;
	}
}