#nullable enable

#region
var _input = Array.Empty<string>();
var _iter = 0;
string String()
{
    while (_iter >= _input.Length) (_input, _iter) = (Console.ReadLine()!.Split(' '), 0);
    return _input[_iter++];
}
T I<T>() where T : IParsable<T> => T.Parse(String(), null);
#endregion

var s = "390,429,468,507,546".Split(',').Select(int.Parse).ToArray();
var l = I<int>() - 1;
var a = String()[0];
if (a == 'B') l++;
Console.WriteLine(s[l]);