import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		char[] s = sc.next().toCharArray();
		sc.close();

		if (n == 1 && s[0] == 'w') {
			System.out.println("No");
			return;
		}

		for (int i = n - 1; i >= 0; i--) {
			if (s[i] != 'w' && s[i] != 'a' && s[i] != 'o' && s[i] != 'n' && s[i] != '?') {
				System.out.println("No");
				return;
			}
			if (s[i] == 'a' || s[i] == 'o') {
				if (i == 0 || s[i - 1] != 'w' && s[i - 1] != '?') {
					System.out.println("No");
					return;
				}
				s[i - 1] = 'w';
			}
			if (s[i] == 'w' || s[i] == 'n') {
				if (i != 0 && s[i - 1] == 'w') {
					System.out.println("No");
					return;
				}
			}
		}
		System.out.println("Yes");
	}
}