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 Class1{
	public static void main(String[] args) {
		long n,m;
		long r;
		Scanner in = new Scanner(System.in);
		m = in.nextLong();
//		while(n>=0) {
//			r = n%10;
//			System.out.println(r);
//			if(r!=4||r!=7) {
//				System.out.println("NO");
//				break;
//			}
//			if(r==4||r==7) {
//				n =n/10;
//				System.out.println("asdjf");
//				continue;
//			}
//		}
		n=m;
		int d=0;
		while(m!=0) {
			m = m/10;
			d++;
		}
		int i;
		int h = 0;
		int f=0,s=0;
//		System.out.println(n);
		long [] a =new long[20];
		for(i = 0;i<d;i++) {
			a[i] = n%10;
			n = n/10;
		}
//		System.out.println(d);
		for(i =0 ;i<d;i++) {		
	
			if(a[i]==4){
				f++;
			}
			if(a[i]==7){
				s++;
			}
			
		}
		f=f+s;
		if((f==4||f==7)&&f!=0) 
			System.out.println("YES");
		else
			System.out.println("NO");
	}
}