#include <bits/stdc++.h>
 
using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  string s;
  cin >> n >> s;
  string ans {"Yes\n"};
  for (int i=n-1;0<=i;--i) {
    if (s[i] == 'w') {
      if (i == n-1) ans = "No\n";
      else if (s[i+1] == '?' || s[i+1] == 'o' || s[i+1] == 'a');
      else ans = "No\n";
    } else if (s[i] == 'a') {
      if (i == 0) ans = "No\n";
      else if (s[i-1] == 'w' || s[i-1] == '?') s[i-1] = 'w';
      else ans = "No\n";
    } else if (s[i] == 'o') {
      if (i == 0) ans = "No\n";
      else if (s[i-1] == 'w' || s[i-1] == '?') s[i-1] = 'w';
      else ans = "No\n";
    } else if (s[i] == 'n') {
    } else if (s[i] == '?') {
    } else {
      ans = "No\n";
    }
  }
  cout << ans;
}