//Normal-2

#define _GLIBCXX_DEBUG
#define ll long long
#include <bits/stdc++.h>
using namespace std;
using Graph = vector<vector<int>>;

void p(auto a){
  cout << a;
}

void ps(auto a){
  cout << a << " ";
}

void ps(){
  cout << " ";
}

void pl(auto a){
  cout << a << endl;
}

void pl(){
  cout << endl;
}

void fix15(){
  cout << fixed << setprecision(15);
}

void YES(){
  pl("YES");
}

void NO(){
  pl("NO");
}

void Yes(){
  pl("Yes");
}

void No(){
  pl("No");
}

void yes(){
  pl("yes");
}

void no(){
  pl("no");
}

//Normal-2
int main(){
  int N; cin >> N;
  string S; cin >> S;

  for(int i = 1; i < N-1; i++){
    bool flag = true;
    
    if(S[i-1] != 'w' and S[i-1] != 'a' and S[i-1] != 'o' and S[i-1] != 'n' and S[i-1] != '?') flag = false;
    if(S[i+1] != 'w' and S[i+1] != 'a' and S[i+1] != 'o' and S[i+1] != 'n' and S[i+1] != '?') flag = false;   
    if(S[i-1] == 'w' and S[i] == '?' and S[i+1] == 'a') flag = false;

    if(!flag){
      No();

      return 0;
    }
  }

  Yes();
}