using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[] NMi => ReadLine().Split().Select(c => int.Parse(c) - 1).ToArray();
    static int[][] NMap(int n) => Enumerable.Repeat(0, n).Select(_ => NMi).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, m) = (c[0], c[1]);
        var a = NList;
        var ans = Kado(n, m, a);
        if (ans[0] == -1)
        {
            WriteLine("No");
        }
        else
        {
            WriteLine("Yes");
            WriteLine(string.Join(" ", ans));
        }
    }
    static int[] Kado(int n, int m, int[] a)
    {
        for (var i = 0; i < n; ++i) for (var j = 1; j < 3; ++j)
        {
            if (i + j < n && a[i] == a[i + j]) return new int[] { -1 };
        }
        var tree = new List<int>[m];
        for (var i = 0; i < m; ++i) tree[i] = new List<int>();
        var refs = new int[m];
        for (var i = 0; i + 1 < n; ++i)
        {
            if (i % 2 == 0)
            {
                tree[a[i] - 1].Add(a[i + 1] - 1);
                ++refs[a[i + 1] - 1];
            }
            else
            {
                tree[a[i + 1] - 1].Add(a[i] - 1);
                ++refs[a[i] - 1];
            }
        }
        var q = new Queue<int>();
        for (var i = 0; i < m; ++i) if (refs[i] == 0) q.Enqueue(i);
        var num = 1;
        var ans = new int[m];
        while (q.Count > 0)
        {
            var cur = q.Dequeue();
            ans[cur] = num;
            ++num;
            foreach (var next in tree[cur])
            {
                --refs[next];
                if (refs[next] == 0)
                {
                    q.Enqueue(next);
                }
            }
        }
        if (ans.Any(ai => ai == 0)) return new int[] { -1 };
        return ans;
    }
}