#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct X{
	char ch;
	int h;
	int w;
	X(char Ch,int H,int W){
		ch=Ch;
		h=H;
		w=W;
	}
	bool operator>(X &x){
		if (h>x.h){
			return true;
		}else if (h==x.h){
			return w<x.w;
		}
		return false;
	}
};
bool Bigger(X &l,X& r){
	return l>r;
}
int main(int argc, char* argv[])
{
	int Ha,Wa;
	int Hb,Wb;
	int Hc,Wc;


	cin>>Ha>>Wa;
	cin>>Hb>>Wb;
	cin>>Hc>>Wc;
	X x1('A',Ha,Wa);
	X x2('B',Hb,Wb);
	X x3('C',Hc,Wc);
	
	vector<X> x;
	x.push_back(x1);
	x.push_back(x2);
	x.push_back(x3);
	sort(x.begin(),x.end(),Bigger);
	for (int i=0;i<x.size();i++){
		cout<<x[i].ch<<endl;
	}
	return 0;
}