#include<iostream>
#include<queue>
using namespace std;
int main() {
	priority_queue<pair<int, char>>pq;
	pair<int, char>p;
	cin >> p.first;
	p.second = 'A';
	pq.push(p);
	cin >> p.first;
	p.second = 'B';
	pq.push(p);
	cin >> p.first;
	p.second = 'C';
	pq.push(p);
	cout << pq.top().second << endl;
	pq.pop();
	cout << pq.top().second << endl;
	pq.pop();
	cout << pq.top().second << endl;
	pq.pop();
	return 0;
}