#include<iostream>
using namespace std;
int main() {
	int A, B, C;;
	cin >> A;
	cin >> B;
	cin >> C;
	char res[3] = { 'A','B','C' };
	int t;
	if (A < B) {
		t = B;
		B = A;
		A = t;
		t = res[1];
		res[1] = res[0];
		res[0] = t;
	}
	if (B < C) {
		t = C;
		C = B;
		B = t;
		t = res[2];
		res[2] = res[1];
		res[1] = t;
	}
	if (A < B) {
		t = B;
		B = A;
		A = t;
		t = res[1];
		res[1] = res[0];
		res[0] = t;
	}
	for (int i = 0; i < 3; i++) {
		cout << res[i] << endl;
	}
	return 0;
}