#include <bits/stdc++.h>
using namespace std;

typedef tuple< int, string > height;

int main(void)
{
  int a, b, c;
  cin >> a >> b >> c;
  vector< height > h(3);
  h[0] = make_tuple(a, "A");
  h[1] = make_tuple(b, "B");
  h[2] = make_tuple(c, "C");
  sort(h.begin(), h.end());
  cout << get<1>(h[2]) << endl << get<1>(h[1]) << endl << get<1>(h[0]) << endl;
  return 0;
}