#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	int H[3], W[3];
	REP(i, 3) cin >> H[i] >> W[i];
	vector<int> ord(3);
	iota(ALL(ord), 0);
	sort(ALL(ord), [&](int x, int y) {
		if (H[x] == H[y]) return W[x] < W[y];
		return H[x] > H[y];
	});
	REP(i, 3) printf("%c\n", ord[i] + 'A');
}