#include<bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define fore(i,a) for(auto &i:a)
using namespace std;

int main() {
    string s = "ABC";
    int x;
    vector<pair<int, char>> v;
    rep(i, 3) {
        cin >> x;
        v.push_back({ x, s[i] });
    }
    sort(v.begin(), v.end(),greater<pair<int,char>>());
    fore(p,v) cout << p.second << endl;
}