Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.

Unfortunately, not all numbers are lucky. Petya calls a number nearly lucky if the number of lucky digits in it is a lucky number. He wonders whether number n is a nearly lucky number.

Input

The only line contains an integer n (1 ≤ n ≤ 1018).

Please do not use the %lld specificator to read or write 64-bit numbers in С++. It is preferred to use the cin, cout streams or the %I64d specificator.

Output

Print on the single line "YES" if n is a nearly lucky number. Otherwise, print "NO" (without the quotes).

Examples

Input

40047


Output

NO


Input

7747774


Output

YES


Input

1000000000000000000


Output

NO

Note

In the first sample there are 3 lucky digits (first one and last two), so the answer is "NO".

In the second sample there are 7 lucky digits, 7 is lucky number, so the answer is "YES".

In the third sample there are no lucky digits, so the answer is "NO".

/*      */

import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
    static class FastReader 
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new InputStreamReader(System.in)); 
        }
        String next()
        {
            while (st == null || !st.hasMoreElements())
            { 
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken(); 
        }
        int nextInt()
        {
            return Integer.parseInt(next());
        }
        long nextLong()
        {
            return Long.parseLong(next());
        }
        double nextDouble()
        {
            return Double.parseDouble(next());
        }
        String nextLine()
        {
            String str = ""; 
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }


public static long sumofdigits( long n ) {
    long sum_digits = 0;
    while(n>0){
        sum_digits += n%10;
        n /= 10;
    }
    return sum_digits;
}


public static long gcd(long n,long sum) {
    if(sum==0){
        return n;
    }
    else{
        return gcd(sum, n%sum);
}
}

/* ----- MAIN STARTS FROM HERE ------- */ 

    public static void main(String[] args)
    {
        FastReader s=new FastReader();
        long n = s.nextLong();
        int count=0;

        while(n>0){
            long a = n%10;
            if(a==4 || a==7){
                count++;
            }
            n /= 10;
        }


        if(count==4 || count==7){
            System.out.println("YES");
        }
        else{
            System.out.println("NO");
        }
    }
}