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 Main {
	
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		String number = input.next();
		int luckyDigits;
		
		luckyDigits = isLuckyNumber("" + number);
		
		if(isLuckyNumber(luckyDigits + "") == (luckyDigits + "").length())
			System.out.println("YES");
		else
			System.out.println("NO");
		
		input.close();
	}
	
	public static int isLuckyNumber(String number) {
		char digit;
		int count = 0;
		
		for(int i = 0; i < number.length(); i++) {
			digit = number.charAt(i);
			
			if((digit == '4') || (digit == '7'))
				count++;
		}
		
		return count;
	}
}

