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 A_NearlyLuckyNumber {

	public static void main(String[] args) {
		A_NearlyLuckyNumber problem = new A_NearlyLuckyNumber();
		problem.solve();
	}

	private void solve() {
		Scanner sc = new Scanner(System.in);
		String n = sc.next();
		
		long total = 0;
		for (int i = 0; i < n.length(); i++) 
			if(n.charAt(i) == '4' || n.charAt(i) == '7')total++;
		if (lucky(total)) System.out.println("YES");
		else System.out.println("NO");
	}

	private boolean lucky(long total) {
		String w = Long.toString(total);
		for (int i = 0; i < w.length(); i++) {
			if(w.charAt(i) != '4' && w.charAt(i) != '7') return false;
		}
		return true;
	}
}