#include <bits/stdc++.h>
using LL = long long;
const LL MOD = 1e9+9;
using namespace std;



int main(){
    int A,B,C;cin >> A >> B >> C;
    if(max({A,B,C}) == A){
        cout<<"A"<<endl;
        return 0;
    }
    if(max({A,B,C}) == B){
        cout<<"B"<<endl;
        return 0;
    }
    if(max({A,B,C}) == C){
        cout<<"C"<<endl;
    }
}

