import java.io.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        boolean nonp[] = new boolean[5000001];
        nonp[1] = true;
        for(int i = 2; i < 5000001; i++){
            if(nonp[i]) continue;
            for(int j = i+i; j < 5000001; j += i){
                nonp[j] = true;
            }
        }
        int t = Integer.parseInt(br.readLine());
        while(t-- > 0){
            String[] line = br.readLine().split(" ");
            long a = Long.parseLong(line[0]);
            int p = Integer.parseInt(line[1]);
            System.out.println(nonp[p] ? -1 : a%p==0 ? 0 : 1);
        }
    }
}