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.awt.image.ImagingOpException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.sql.BatchUpdateException;

/**
 * Created by shubheksha on 18/3/15.
 */
public class P110A {
    public static void main(String[] args) throws IOException{
        BufferedReader o = new BufferedReader(new InputStreamReader(System.in));
        long n = Long.parseLong(o.readLine());
        int count = 0;
        while(n!=0){
            if(n%10 == 4 || n%10 == 7)
                count++;
            n/=10;
      //      System.out.println(count);
        }
        boolean flag;
        if(count != 0)
            flag= true;
        else
            flag = false;
        while(count!=0){
            if(count%10 != 4 && count%10 != 7) {
                    flag = false;
                    break;

            }
            count/=10;
        }
        if(flag)
            System.out.println("YES");
        else
            System.out.println("NO");
    }

}
