题解 | #小红的取模构造#

import java.io.*;
import java.util.*;
import java.math.BigInteger;

public class Main {
    static void solve() {
        long a = in.nextLong(), b = in.nextLong();
        if(a==0&&b==0) {
            out.println("1 1");
        }else if(a==0) {
            out.println(b*2+" "+b);
        }else if(b==0) {
            out.println(a+" "+2*a);
        }else if(a>b) {
            out.println(a+" "+(a+b));
        }else if(a<b) {
            out.println((a+b)+" "+b);
        }else {
            out.println("-1 -1");
        }
    }

    public static void main(String[] args) {
        int T = in.nextInt();
        while(T-->0) {
            solve();
        }
        out.flush();
    }

    static FastReader in = new FastReader();
    static PrintWriter out = new PrintWriter(System.out);

    static class FastReader {
        static BufferedReader br;
        static StringTokenizer st;

        FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            String str = "";
            while (st == null || !st.hasMoreElements()) {
                try {
                    str = br.readLine();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                st = new StringTokenizer(str);
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }
    }
}