#include <iostream>
using namespace std;

int main() {
    int a, b, c;

    cin >> a >> b >> c;

    if(a > b) {
        if (a > c) {
            cout << "A" << endl;
        } else {
            cout << "C" << endl;
        }
    } else {
        if (b > c) {
            cout << "B" << endl;
        } else {
            cout << "C" << endl;
        }
    }
}


