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.*;
public class Nearly_Lucky_Number {

	static Scanner in = new Scanner(System.in);
	public static void main(String[] args) {
	
		String input = in.next();
		int luckNumberCount = 0;
		
		for(int i = 0; i < input.length(); i++){
			if(input.charAt(i) == '4' || input.charAt(i) == '7')
				luckNumberCount++;
		}
		
		
		boolean luckNum = true;
		
		if(luckNumberCount == 0)
			luckNum = false;else{
				while(luckNumberCount>0){
					int remainder = luckNumberCount%10;
					luckNumberCount/=10;
					if(remainder != 7 && remainder != 4){
						luckNum = false;break;
					}//if
				}//while
			}
		
		

		if(luckNum == true)
			System.out.println("YES");else
				System.out.println("NO");
		
	}

}
