require 'tsort'

class Hash
  include TSort
  alias tsort_each_node each_key
  def tsort_each_child(node, &block)
    fetch(node).each(&block)
  end
end

N, M = gets.split.map(&:to_i)
A = gets.split.map(&:to_i)
E = Hash.new { |h, k| h[k] = [] }

A.each_cons(3) do |a, _, c|
  if a == c
    puts "No"
    exit
  end
end

A.each_cons(2).with_index do |(u, v), i|
  if u == v
    puts "No"
    exit
  end

  if i.even?
    E[u] << v
  else
    E[v] << u
  end
end

1.upto(M) do |i|
  E[i] = E[i].uniq
end

ans = Array.new(M, -1)

begin
  E.tsort.each.with_index(1) do |u, a|
    ans[u - 1] = a
  end

  puts "Yes"
  puts ans.join(" ")
rescue TSort::Cyclic => e
  puts "No"
end