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 HelloWorld {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long input = sc.nextLong();				//입력값
		//판단해주는 메소드 호출. 스트링 반환
		String result = checkLuck(input);
		//스트링값 출력.
		System.out.println(result);
		sc.close();
	}//main
	
	
	//입력을 받으면 4와 7의 갯수를 세서, 4나 7이 나오면 럭키넘버출력.
		static String checkLuck(long input){
			int cnt = 0;
			String str = Long.toString(input);
			for(int i = 0 ; i< str.length() ; i++ ){
				if(str.charAt(i) == '4'|| str.charAt(i) =='7')
					cnt++;
			}
			String result="";
			if(cnt == 4 || cnt == 7){
				result = "YES";
			}else{
				result = "NO";
			}
			
			return result;
		}
}//class
