// 別解（貪欲法）
//   (1) w? -> wa
//   (2) ?a -> wa
//   (3) ?o -> wo
//   (4)  ? -> n

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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(15);

    int N;
    cin >> N;
    string S;
    cin >> S;

    string T = "waon?";
    for (auto s : S) {
        if (T.find(s) == string::npos) {
            cout << "No" << '\n';
            return 0;
        }
    }

    for (int i = 0; i + 1 < N; i++) {
        if (S[i] == 'w' && S[i + 1] == '?') {
            S[i + 1] = 'a';
        }
        if (S[i] == '?' && (S[i + 1] == 'a' || S[i + 1] == 'o')) {
            S[i] = 'w';
        }
    }
    for (auto& s : S) {
        if (s == '?') { s = 'n'; }
    }

    vector<string> patterns = {"wa", "wo", "n"};
    auto is_wawon = [&](string S) -> bool {
        int i = 0;
        while (true) {
            if (i == N) { return true; }
            bool found = false;
            for (auto p : patterns) {
                int n = p.size();
                if (i + n <= N && S.substr(i, n) == p) {
                    i += n;
                    found = true;
                    break;
                }
            }
            if (not found) { break; }
        }
        return false;
    };

    bool ok = is_wawon(S);
    string ans = (ok ? "Yes" : "No");
    cout << ans << '\n';

    return 0;
}