using System;
using System.Linq;

public class P0570 {
    public static void Main() {
        var a = int.Parse(Console.ReadLine().Trim());
        var b = int.Parse(Console.ReadLine().Trim());
        var c = int.Parse(Console.ReadLine().Trim());
        foreach(string s in new int[]{a,b,c}.Zip(new string[]{"A", "B", "C"}, (h, n) => new { height = h, name = n })
            .OrderByDescending(pair => pair.height)
            .Select(pair => pair.name)
        ) {
            Console.WriteLine(s);
        }
    }
}