#include<iostream>
using namespace std;
int b10tob2(int x) {
int k = 0;
while (x != 0) {
k += (x % 2);
x /= 2;
}
return k;
}
int main() {
int n, v[2][101];
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> v[0][i];
v[1][i] = b10tob2(v[0][i]);
}
for (int i = 1; i <= n - 1; i++)
for (int j = i + 1; j <= n; j++)
if (i != j && v[1][i] == v[1][j])
cout << v[0][i] << ' ' << v[0][j] << ', ';
return 0;
}