#include <bits/stdc++.h>
using namespace std;
unsigned long long X, Y, A, B;
int x[100], y[100], z[100];
int main() {
  scanf("%I64d %I64d", &X, &Y);
  A = X, B = Y;
  if (X == Y) {
    cout << 0 << " " << X << endl;
  } else {
    for (long long i = 0; i < 64; i++) {
      x[i] = X % 2;
      X /= 2;
      y[i] = Y % 2;
      Y /= 2;
    }
    for (int i = 1; i < 64; i++) {
      if (y[i] == 0) {
        if (x[i] == 1) z[i] = 1;
      }
      if (y[i] == 1) {
        if (x[i] == 0) z[i] = 1;
      }
    }
    for (int i = 0; i < 64; i++) {
      if (y[i] == 1) Y += (1LL << i);
      if (y[i] == 0 && z[i + 1] == 1) {
        Y += (1LL << i);
        X += (1LL << i);
      }
    }
    if (X + Y != A || (X ^ Y) != B)
      cout << -1 << endl;
    else
      cout << X << " " << Y << endl;
  }
  return 0;
}
