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.io.InputStreamReader;
import java.util.Scanner;

public class AlmostLuckyNumber {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(new InputStreamReader(System.in));
		String input = null;
		
        try {
        	input = scanner.next();
        } catch(Exception e){
            System.err.println("exception=" + e.toString());
            System.exit(-1);
        } finally {
        	scanner.close();
        }
        
        int count4 = 0, count7 = 0;
        for (int i = 0; i < input.length(); i++) {
        	switch (input.charAt(i)) {
        	case '4':
        		count4++;
        		break;
        	case '7':
        		count7++;
        		break;
        	default:
        		break;
        	}
        }
        
        int luckySum = count4 + count7;
        if ((luckySum==4 ||
        				luckySum==7))
        	System.out.println("YES");
        else
        	System.out.println("NO");
	}
}
