#include <bits/stdc++.h>
using namespace std;
const int N = 65;
int f[N][2], g[N][2];
unsigned long long a, b, x;
int main() {
  cin >> a >> b;
  memset(f, -1, sizeof(f));
  f[0][0] = 0;
  for (int i = 1; i <= 64; i++) {
    int p = a >> i - 1 & 1, q = b >> i - 1 & 1;
    if (f[i - 1][0] >= 0) {
      if (p == 0 && q == 0) f[i][0] = 0, f[i][1] = 1, g[i][0] = g[i][1] = 0;
      if (p == 1 && q == 1) f[i][0] = 0, g[i][0] = 0;
    }
    if (f[i - 1][1] >= 0) {
      if (p == 0 && q == 1) f[i][1] = 0, g[i][1] = 1;
      if (p == 1 && q == 0) f[i][0] = 0, f[i][1] = 1, g[i][0] = g[i][1] = 1;
    }
  }
  if (f[64][0] < 0) {
    cout << -1;
    return 0;
  }
  for (int i = 64, j = 0; i >= 1; i--) {
    x = x * 2 + f[i][j];
    j = g[i][j];
  }
  cout << x << ' ' << a - x;
}
