#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<(b);++i)
#define erep(i,a,b) for(int i=a;i<=(int)(b);++i)
#define per(i,a,b) for(int i=(a);i>(b);--i)
#define eper(i,a,b) for(int i=(a);i>=b;--i)
#define pb push_back
#define mp make_pair
#define INF 100100100100
#define MOD 1000000007
#define ALL(x) begin(x),end(x)
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using vii = vector<int>;
using vll = vector<ll>;
template<class T>using vv = vector<T>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
int dy[]={0, 0, 1, -1};
int dx[]={1, -1, 0, 0};
int gcd(int a,int b){return b?gcd(b,a%b):a;}
int lcm(int a,int b){return a/gcd(a, b)*b;}

bool cmp (const tuple<int, int, char> &a, const tuple<int, int, char> &b) {
  if (get<0>(a) != get<0>(b)) return get<0>(a) > get<0>(b);
  return get<1>(a) < get<1>(b);
}

vector<tuple<int, int, char> > h;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
    int ha, hb, hc, wa, wb, wc;
    cin >> ha >> wa >> hb >> wb >> hc >> wc;
    h.pb({ha, wa, 'A'}); h.pb({hb, wb, 'B'}); h.pb({hc, wc, 'C'});
    sort(ALL(h), cmp);
    for (auto x : h) cout << get<2>(x) << endl;
    return 0;
}