#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i, n) for(int i=0;i<(n);++i)
#define rep1(i, n) for(int i=1;i<=(n);i++)
#define ll long long
using mint = modint998244353;
using P = pair<ll,ll>;
using lb = long double;
using T = tuple<ll, ll, ll>;
#ifdef LOCAL
#  include <debug_print.hpp>
#  define dbg(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define dbg(...) (static_cast<void>(0))
#endif

int main()
{
    int n;
    string s;
    cin >> n >> s;
    rep(i,n){
        if(s[i]!='w' && s[i]!='a' && s[i]!='o' && s[i]!='n' && s[i]!='?'){
            cout<<"No"<<endl;
            return 0;
        }
    }
    vector<bool> used(n);
    rep(i,n){
        if(s[i]=='w') {
            if(i+1<n) {
                if(s[i+1]=='a' || s[i+1]=='o') continue;
                if(s[i+1]=='?') used[i+1] = true;
                else{
                    cout<<"No"<<endl;
                    return 0;
                }
            }
            else{
                cout<<"No"<<endl;
                return 0;
            }
        }
        else if(s[i]=='a' || s[i]=='o'){
            if(i-1>=0) {
                if(s[i-1]=='w') continue;
                else if(s[i-1]!='?' || used[i-1]){
                    cout<<"No"<<endl;
                    return 0;
                }
            }
            else{
                cout<<"No"<<endl;
                return 0;
            }
        }
    }
    cout<<"Yes"<<endl;
    return 0;
}