#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  int n;
  string s;
  cin >> n >> s;
  vector dp(n + 1, vector<bool>(2, false));
  dp[0][0] = true;
  rep(i, n) {
    switch (s[i]) {
      case 'w':
        if (dp[i][0]) dp[i + 1][1] = true;
        break;
      case 'a':
        if (dp[i][1]) dp[i + 1][0] = true;
        break;
      case 'o':
        if (dp[i][1]) dp[i + 1][0] = true;
        break;
      case 'n':
        if (dp[i][0]) dp[i + 1][0] = true;
        break;
      case '?':
        if (dp[i][0]) dp[i + 1][0] = dp[i + 1][1] = true;
        if (dp[i][1]) dp[i + 1][0] = true;
        break;
    }
  }
  cout << (dp[n][0] ? "Yes" : "No") << endl;
  return 0;
}