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;

public class Home{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        int j = 0;
        boolean a = true;
        String f;
        for (int i = 0; i < s.length(); ++i) {
            if (s.charAt(i) == '4' ||s.charAt(i) == '7') {
                ++j;
            }
        }
        f = String.valueOf(j);
        for (int i = 0; i < f.length(); ++i) {
            if (String.valueOf(f.charAt(i)).equals("7")) {
            }
            else if (String.valueOf(f.charAt(i)).equals("4")) {
            }
            else {
                a = false;
            }
        }
        if (!a) {
            System.out.println("NO");
        }
        else {
            System.out.println("YES");
        }
    }
}