#include using namespace std; #ifdef DEBUG_ #include #else #define dump(...) #endif #define FastIO cin.tie(nullptr), ios_base::sync_with_stdio(false); #define rep(i, n) for (int i = 0; (int)i < n; ++i) #define repa(i, a, n) for (int i = a; (int)i < n; ++i) #define rrep(i, n) for (int i = n; (int)i >= 0; --i) #define rrepa(i, a, n) for (int i = a; (int)i >= n; --i) #define EACH(x, a) for (auto& x : a) #define output(msg) cout << (msg) << '\n' #define die(msg) \ do { \ cout << msg << endl; \ exit(0); \ } while (0) template void read(vector& v); template void read(array& a); template void read(T& x) { cin >> x; } void read(double& d) { string t; read(t); d = stod(t); } void read(long double& d) { string t; read(t); d = stold(t); } template void read(H& h, T&... t) { read(h); read(t...); } template void read(vector& x) { EACH(a, x) read(a); } template void read(array& x) { EACH(a, x) read(a); } template bool chmax(T& a, const T& b) { return ((a < b) ? (a = b, true) : (false)); } template bool chmin(T& a, const T& b) { return ((a > b) ? (a = b, true) : false); } using llint = long long int; bool valid(char ch) { return ch == 'w' || ch == 'a' || ch == 'o' || ch == 'n' || ch == '.'; } int main() { FastIO; int n; read(n); string s; read(s); int len = (int)s.size(); dump(s); // . means 'a' or 'o' rep(i, len - 1) { if (s[i] == 'w' && s[i + 1] == '?') { s[i + 1] = '.'; } } // 'wa' 'wo' 'w.' repa(i, 1, len) { char prev = s[i - 1]; if (s[i] == 'o' || s[i] == 'a' || s[i] == '.') { if (prev == '.' || prev == 'o' || prev == 'a') { die("No"); } else if (prev == '?') { s[i - 1] = 'w'; } else if (prev == 'w') { continue; } else { die("No"); } } } rep(i, len) { if (s[i] == '?') s[i] = 'n'; } dump(s); // check rep(i, len - 1) { char cur = s[i]; char nxt = s[i + 1]; if (!valid(cur)) die("No"); if (cur == 'w') { if (!(nxt == 'a' || nxt == 'o' || nxt == '.')) die("No"); } } dump(s); output("Yes"); }