#include <iostream>
#include <vector>
#include <algorithm>
#include <math.h>
#include <map>
#include <set>

#define ALL(x) (x).begin(),(x).end()
#define RALL(x) (x).rbegin(),(x).rend()
#define REP(i,a,n) for(int i = (a);i < (n);i++)
#define PI 3.14159265359
#define MOD 1000000007

using namespace std;

int main(){
    vector<pair<pair<int, int>, char>> ans;
    int HA,WA,HB,WB,HC,WC;
    cin >> HA >> WA >> HB >> WB >> HC >> WC;
    ans.push_back({{HA,-WA},'A'});
    ans.push_back({{HB,-WB},'B'});
    ans.push_back({{HC,-WC},'C'});
    sort(ALL(ans));
    printf("%c\n%c\n%c\n",ans[2].second,ans[1].second,ans[0].second);
    return 0;
}