#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
using namespace std;
struct X{
	int h;
	char ch;
	void Print(){
		cout<<ch<<endl;
	}
};
bool Comp(X&l,X&r){
	return l.h>r.h;
}
int main(int argc, char* argv[])
{
	int Ha,Hb,Hc;
	cin>>Ha>>Hb>>Hc;
	vector<X> P(3);
	P[0].h=Ha;
	P[0].ch='A';
	P[1].h=Hb;
	P[1].ch='B';
	P[2].h=Hc;
	P[2].ch='C';
	sort(P.begin(),P.end(),Comp);
	for (int i=0;i<3;i++){
		P[i].Print();
	}
	return 0;
}