cf 1612A

#include<bits\stdc++.h>

using namespace std;

int main()
{
    int t;
    cin >> t;
    while(t--)
    {
        int x, y, i, j;
        cin >> x >> y;
        bool found = false;
        for(i = 0; i <= 50; i++)
        {
            for(j = 0; j <= 50; j++)
            {
                if(2*(i + j) == x + y && 2*(abs(x-i) + abs(y-j)) == x+y)
                {
                    found = true;
                    x = i, y = j;
                    break;
                }
            }
            if(found) break;
        }
        if(!found) x = -1, y = -1;
        printf("%d %d\n", x, y);
    }
}