N = gets.to_i
S = gets.chomp

dp = Array.new(N) { Array.new(26, false) }
if S[0] == '?'
  26.times { |j| dp[0][j] = true }
end
if S[0] == 'n'
  dp[0]['n'.ord - 'a'.ord] = true
end
if S[0] == 'w'
  dp[0]['w'.ord - 'a'.ord] = true
end
if S[0] == 'a' || S[0] == 'o'
  puts "No"
  exit
end

1.upto(N - 1) do |i|
  0.upto(25) do |j|
    if dp[i - 1][j]
      if j == 'w'.ord - 'a'.ord
        if S[i] == 'a'
          dp[i]['a'.ord - 'a'.ord] = true
        end
        if S[i] == 'o'
          dp[i]['o'.ord - 'a'.ord] = true
        end
        if S[i] == '?'
          dp[i]['a'.ord - 'a'.ord] = true
          dp[i]['o'.ord - 'a'.ord] = true
        end
      else
        if S[i] == 'w'
          dp[i]['w'.ord - 'a'.ord] = true
        end
        if S[i] == 'n'
          dp[i]['n'.ord - 'a'.ord] = true
        end
        if S[i] == '?'
          dp[i]['w'.ord - 'a'.ord] = true
          dp[i]['n'.ord - 'a'.ord] = true
        end
      end
    end
  end
end

ans = false
ans = true if dp[N - 1]['a'.ord - 'a'.ord]
ans = true if dp[N - 1]['o'.ord - 'a'.ord]
ans = true if dp[N - 1]['n'.ord - 'a'.ord]

if ans
  puts "Yes"
else
  puts "No"
end