namespace AtCoder; #nullable enable using System.Numerics; static class Extensions { public static T[] Repeat(this int time, Func F) => Enumerable.Range(0, time).Select(_ => F()).ToArray(); } class AtCoder { object? Solve() { var n = Input(); var k = Input(); if (n >= k) return 'y'; var lv = 1; var ld = 4L; var ls = 3L; var ly = n - 1; while (ld + ls + ly < k) { lv++; (ld, ls) = (ld * 4, ld * 3 + ls); ly--; } var yuusaan = "yuusaan"; k -= ly; k--; while (true) { if (lv == 1) return yuusaan[(int)k]; lv--; var nld = ld / 4; (ld, ls) = (nld, ls - nld * 2); var ln = ld + ls; 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(); 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() where T : IParsable => T.Parse(String(), null); int Int() => Input(); 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(); } }