Problem: Overlooking the captivating blend of myriads of vernal hues, Arkady the painter lays out a long, long canvas.

Arkady has a sufficiently large amount of paint of three colours: cyan, magenta, and yellow. On the one-dimensional canvas split into n consecutive segments, each segment needs to be painted in one of the colours.

Arkady has already painted some (possibly none or all) segments and passes the paintbrush to you. You are to determine whether there are at least two ways of colouring all the unpainted segments so that no two adjacent segments are of the same colour. Two ways are considered different if and only if a segment is painted in different colours in them.

Input

The first line contains a single positive integer n (1 ≤ n ≤ 100) — the length of the canvas.

The second line contains a string s of n characters, the i-th of which is either 'C' (denoting a segment painted in cyan), 'M' (denoting one painted in magenta), 'Y' (one painted in yellow), or '?' (an unpainted one).

Output

If there are at least two different ways of painting, output "Yes"; otherwise output "No" (both without quotes).

You can print each character in any case (upper or lower).

Examples

Input

5
CY??Y


Output

Yes


Input

5
C?C?Y


Output

Yes


Input

5
?CYC?


Output

Yes


Input

5
C??MM


Output

No


Input

3
MMY


Output

No

Note

For the first example, there are exactly two different ways of colouring: CYCMY and CYMCY.

For the second example, there are also exactly two different ways of colouring: CMCMY and CYCMY.

For the third example, there are four ways of colouring: MCYCM, MCYCY, YCYCM, and YCYCY.

For the fourth example, no matter how the unpainted segments are coloured, the existing magenta segments will prevent the painting from satisfying the requirements. The similar is true for the fifth example.

Solution (in JAVA):

Solution:
import  java.io.IOException;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.util.*;
import java.math.*;
import java.io.*;

public class hacker
{  

    /*Fatt Gyi Bhai*/
    //Dekh le mera code
    public static boolean[] sieve(long n)
    {
        boolean[] prime = new boolean[(int)n+1];
        Arrays.fill(prime,true);
        prime[0] = false;
        prime[1] = false;
        long m = (long)Math.sqrt(n);
        for(int i=2;i<=m;i++)
        {
            if(prime[i])
            {
                for(int k=i*i;k<=n;k+=i)
                {
                    prime[k] = false;
                }
            }
        }
        return prime;
    } 

    
    static long GCD(long a,long b)
    {
        if(a==0 || b==0)
        {
            return 0;
        }
        if(a==b)
        {
            return a;
        }
        if(a>b)
        {
            return GCD(a-b,b);
        }
        return GCD(a,b-a);
    }

    static long CountCoPrimes(long n)
    {
        long res = n;
        for(int i=2;i*i<=n;i++)
        {
            if(n%i==0)
            {
                while(n%i==0)
                {
                    n/=i;
                }
                res-=res/i;
            }
        }
        if(n>1)
        {
            res-=res/n;
        }
        return res;
    }

    static long modularExponentiation(long x,long n,long m)
    {
        long res = 1;
        while(n>0)
        {
            if(n%2==1)
            {
                res = (res*x)%m;
            }
            x =(x*x)%m;
            n/=2;
        }
        return res;
    }

    static long lcm(long a,long b)
    {
        return (a*b)/GCD(a,b);
    }

   
    static long pow(long a,long b)
    {
        long res = 1;
        while(b>0)
        {
            if((b&1)==1)
            {
                res *= a;
            }

            b >>= 1;
            a *=a;
        }
        return res;
    }

   static long modInverse(long A,long M)
   {
    return modularExponentiation(A,M-2,M);
   }
   static long factorial(long n) 
    { 
        String ooo="";
        long res[] = new long[500]; 
  
        // Initialize result 
        res[0] = 1; 
        long res_size = 1; 
  
        
        for (long x = 2; x <= (int)n; x++) 
        {
            res_size = multiply(x, res, res_size); 
        }

        for (int i = (int)res_size - 1; i >= 0; i--) 
        {
            ooo+=res[i];
        }
        return Long.parseLong(ooo);
    } 
   
    static long multiply(long x, long res[], long res_size) 
    { 
        long carry = 0; // Initialize carry 
  
        // One by one multiply n with individual  
        // digits of res[] 
        for (int i = 0; i <(int) res_size; i++) 
        { 
            long prod = res[i] * x + carry; 
            res[i] = prod % 10; // Store last digit of  
                                // 'prod' in res[] 
            carry = prod/10; // Put rest in carry 
        } 
  
        // Put carry in res and increase result size 
        while (carry!=0) 
        { 
            res[(int)res_size] = carry % 10; 
            carry = carry / 10; 
            res_size++; 
        } 
        return res_size; 
    } 

    static void reverse(int[] a)
    {
        int start=0;
        int end = a.length-1;
        while(start<end)
        {
            int temp = a[start];
            a[start] = a[end];
            a[end] = temp;
            start++;
            end--;
        }

    }
  
    public static void main(String[] args) throws IOException
    {
       // in = new Scanner(new File("explicit.in"));
        //out = new PrintWriter("explicit.out");
        new hacker().run();
       
    }


    static int rev(int n)
    {
        int x=0;
        int num = 0;
        while(n>0)
        {
            x = n%10;
            num = num*10+x;
            n/=10;

        }
        return num;
    }

   
    
   
   static Scanner sc = new Scanner(System.in);
    static void run() throws IOException
    {
        int t = ni();
        char[] c = si().toCharArray();
        for(int i=0;i<t-1;i++)
        {
            if(c[i]==c[i+1] && c[i]!='?')
            {
                System.out.println("No");
                return;
            }
        }

        for(int i=0;i<t;i++)
        {
            if(c[i]=='?')
            {
                if(i==0 |i==t-1)
                {
                    System.out.println("YES");
                    return;

                }
                if(c[i+1]=='?')
                {
                    System.out.println("YES");
                    return;
                }
                if(c[i+1]==c[i-1])
                {
                    System.out.println("YES");
                    return;

                }
            }
        }

        System.out.println("No");
        
       // System.out.println("Yes");

        


       

        
    }

    static void print(long a)
    {
        System.out.println(a);
    }

    static int myabs(int n)
    {
        if(n>0)
        {
            return n;
        }
        else
        {
            return 1+abs(n);
        }
    }
   
   
    static void swap(char c,char p)
    {
        char t = c;
        c = p;
        p = t;
    }

    static int max(int n,int m)
    {
        return Math.max(n,m);
    }
    static long min(long n,long m)
    {
        return Math.min(n,m);
    }

    static double nd() throws IOException
    {
        return Double.parseDouble(sc.next());
    }
    static int ni() throws IOException
    {
        return Integer.parseInt(sc.next());
    }

    static long nl() throws IOException
    {
        return Long.parseLong(sc.next());
    }

    static String si() throws IOException
    {
        return sc.next();
    }


  
   
    static int abs(int n)
    {
        return Math.abs(n);
    }
   
    
    
    static class Scanner 
    {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(InputStream s){  br = new BufferedReader(new InputStreamReader(s));}

        public String next() throws IOException 
        {
            while (st == null || !st.hasMoreTokens()) 
            {
                st = new StringTokenizer(br.readLine());
            }
            return st.nextToken();
        }

        public int nextInt() throws IOException {return Integer.parseInt(next());}
        
        public long nextLong() throws IOException {return Long.parseLong(next());}

        public String nextLine() throws IOException {return br.readLine();}

        public boolean ready() throws IOException {return br.ready();}


    }

   


    
}