using System;
using System.Linq;

namespace _571
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] a = new int[3];
            for (int i = 0; i < 3; i++)
            {
                int[] x = Console.ReadLine().Split().Select(int.Parse).ToArray();
                a[i] = x[0] * 1000 - x[1];
            }
            string[] ret = new string[] { "A","B","C" };
            Array.Sort(a,ret); Array.Reverse(ret);
            for (int i = 0; i < 3; i++) Console.WriteLine(ret[i]);
        }
    }
}