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.Scanner;

/**
 *
 * @author Dhrubo
 */
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        
        Scanner sc  = new Scanner(System.in);
        String s = sc.nextLine();
        long l = 0;
        for(int i = 0; i < s.length(); i++)
        {
            if(s.charAt(i) == '4' || s.charAt(i) == '7')
            {
                l++;
            }
        }
        String st = Long.toString(l);
        boolean flag = true;
        for(int p = 0; p < st.length(); p++)
        {
            if(st.charAt(p) == '4' || st.charAt(p) == '7')
            {
                flag = true;
            }
            else
            {
                flag = false;
                break;
            }
        }
        
        if (flag == true)
        {
            System.out.println("YES");
        }
        else
        {
            System.out.println("NO");
        }
    }
    
}

 	   			  	  	  	 	    		 		  	