namespace AtCoder;

#nullable enable

using System.Numerics;

static class Extensions
{
    public static T[] Repeat<T>(this int time, Func<T> F) => Enumerable.Range(0, time).Select(_ => F()).ToArray();
}

class AtCoder
{
    object? Solve()
    {
        var n = Input<long>();
        var k = Input<long>();
        var lv = 1;
        var ld = 4L;
        var ls = 3L;
        while (ld + ls < k)
        {
            lv++;
            (ld, ls) = (ld * 4, ld * 3 + ls);
        }
        var yuusaan = "yuusaan";
        k--;
        while (true)
        {
            if (lv == 1)
            {
                return yuusaan[(int)k];
            }
            lv--;
            (ld, ls) = (ld / 4, ls - ld / 4 * 3);
            var ln = ld + ls;
            if (k == 0)
            {
                return 'y';
            }
            k--;
            if (k < ln)
            {
                continue;
            }
            k -= ln;
            if (k < ln)
            {
                continue;
            }
            k -= ln;
            if (k == 0)
            {
                return 's';
            }
            k--;
            if (k < ln)
            {
                continue;
            }
            k -= ln;
            if (k < ln)
            {
                continue;
            }
            k -= ln;
            if (k == 0)
            {
                return 'n';
            }
        }
    }

    public static void Main() => new AtCoder().Run();
    public void Run()
    {
        var res = Solve();
        if (res != null)
        {
            if (res is bool yes) res = yes ? "Yes" : "No";
            sw.WriteLine(res);
        }
        sw.Flush();
    }

    string[] input = Array.Empty<string>();
    int iter = 0;
    readonly StreamWriter sw = new(Console.OpenStandardOutput()) { AutoFlush = false };

    string String()
    {
        while (iter >= input.Length) (input, iter) = (Console.ReadLine()!.Split(' '), 0);
        return input[iter++];
    }
    T Input<T>() where T : IParsable<T> => T.Parse(String(), null);
    int Int() => Input<int>();
    void Out(object? x, string? separator = null)
    {
        separator ??= Environment.NewLine;
        if (x is System.Collections.IEnumerable obj and not string)
        {
            var firstLine = true;
            foreach (var item in obj)
            {
                if (!firstLine) sw.Write(separator);
                firstLine = false;
                sw.Write(item);
            }
        }
        else sw.Write(x);
        sw.WriteLine();
    }
}