N = gets.to_i
S = gets.chomp

dp = Array.new(N + 1, false)
dp[0] = true

N.times do |i|
  next if not dp[i]

  if (S[i] == 'n' || S[i] == '?')
    dp[i + 1] = true
  end

  if i + 1 <= N && (S[i] == 'w' || S[i] == '?') && (S[i + 1] == 'o' || S[i + 1] == '?')
    dp[i + 2] = true
  end

  if i + 1 <= N && (S[i] == 'w' || S[i] == '?') && (S[i + 1] == 'a' || S[i + 1] == '?')
    dp[i + 2] = true
  end
end

if dp[N]
  puts 'Yes'
else
  puts 'No'
end