#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
using ll = long long ;
using P = pair<int,int> ;
using pll = pair<long long,long long>;
constexpr int INF = 1e9;
constexpr long long LINF = 1e17;
constexpr int MOD = 1000000007;

struct brother{
    int h,w,id;
};

int main(){
    vector<char> ans = {'A','B','C'};
    vector<brother> t(3);
    rep(i,3){
        cin >> t[i].h >> t[i].w;
        t[i].id = i;
    }
    sort(t.begin(),t.end(),[](const brother &l,const brother &r){
        if(l.h==r.h) return l.w < r.w;
        else return l.h > r.h;
    });
    rep(i,3) cout << ans[t[i].id] << endl;
    return 0;
}