#include <cmath>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <functional>
#include <queue>
#include <iostream>
#include <string.h>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <cstdint>
#include <climits>
#include <unordered_set>
#include <sstream>
#include <stack>

using namespace std;

typedef long long int ll;
typedef pair<ll,ll> pii;
typedef tuple<ll,ll,ll> t3;

using namespace std;

struct t{
    int h;
    int w;
    string name;
    
    t(int h_, int w_, string name_)  :h(h_), w(w_), name(name_) { }
};

bool compare(const t& left, const t& right)
{
    if(left.h == right.h)
    {
        return left.w < right.w;
    }
    return left.h > right.h;
}


int main() {
    int a,b,c, aa, bb, cc;
    cin >> a >> aa >> b >> bb >> c >> cc;
    vector<t> p;
    p.emplace_back(a,aa,"A");
    p.emplace_back(b,bb,"B");
    p.emplace_back(c,cc,"C");
    sort(p.begin(), p.end(), compare);
    for(auto e: p)
    {
        cout << e.name << endl;
    }
    return 0;
}