import java.io.*;
import java.util.*;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        char prev = 'n';
        for (char c : sc.next().toCharArray()) {
            if (c == 'w') {
                if (prev == 'w') {
                    System.out.println("No");
                    return;
                }
                prev = 'w';
            } else if (c == 'a' || c == 'o') {
                if (prev != 'w' && prev != '?') {
                    System.out.println("No");
                    return;
                }
                prev = 'a';
            } else if (c == 'n') {
                if (prev == 'w') {
                    System.out.println("No");
                    return;
                }
                prev = 'n';
            } else if (c == '?') {
                if (prev == 'w') {
                    prev = 'a';
                } else {
                    prev = '?';
                }
            } else {
                System.out.println("No");
                return;
            }
        }
        System.out.println("Yes");
    }
}
class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}