#include<bits/stdc++.h>
// #include<atcoder/all>
using namespace std;
// using namespace atcoder;
using lint = long long;
long const mod = 1e9+7;
//long const mod = 998244353;
vector<lint>pp;
void solve(){
    lint a,p;
    scanf("%lld %lld", &a, &p);
    if(!binary_search(pp.begin(),pp.end(), p)){
        printf("%d\n",-1);
        return;
    }
    if(a%p==0){
        printf("%d\n",0);
        return;
    }else{
        printf("%d\n",1);
    }

    



}
int main(){
    pp.push_back(2);
    for(int i=3;i<=5000000;i+= 2){
        bool chk = true;
        for(int j = 0;j < pp.size(); j++){
            if(pp[j] > sqrt(i))break;
            if(i % pp[j] == 0){
                chk = false; 
                break;
            }
        }
        if(chk)pp.push_back(i);
    }
    lint t;
    scanf("%lld", &t);
    for(int i=0;i<t;i++){
        solve();
    }
}