#include <bits/extc++.h>

int main() {
    using namespace std;
    unsigned N;
    string S;
    cin >> N >> S;
    for (auto &&c : S)
        if (c == 'o')
            c = 'a';
    if (S[0] == 'a' || S == "w") {
        cout << "No" << endl;
        return 0;
    }
    for (unsigned i{}; i + 1 < N; ++i) {
        if (S[i] == 'w' && S[i + 1] == '?')
            S[i + 1] = 'a';
        else if (S[i] == '?' && S[i + 1] == 'a')
            S[i] = 'w';
        else if (S[i] == '?')
            S[i] = 'n';

        if (S[i] == 'w' && S[i + 1] != 'a') {
            cout << "No" << endl;
            return 0;
        }
        if (S[i] != 'w' && S[i + 1] == 'a') {
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;
    return 0;
}