using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    public void Solve()
    {
        List<KeyValuePair<string, int>> H = new List<KeyValuePair<string, int>>();
        H.Add(new KeyValuePair<string,int>("A", int.Parse(Console.ReadLine())));
        H.Add(new KeyValuePair<string,int>("B", int.Parse(Console.ReadLine())));
        H.Add(new KeyValuePair<string,int>("C", int.Parse(Console.ReadLine())));

        foreach (var item in H.OrderByDescending(x=>x.Value))
        {
            Console.WriteLine(item.Key);
        }
    }

    static void Main()
    {
        var solver = new Program();
        solver.Solve();
    }
}