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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

/**
 * Created by sahil on 22/10/17.
 */
public class Main {

    public static void main(String[] arg){
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        try {
            String num = reader.readLine();
            int count =0;
            boolean isLucky = true;
            for(int i =0;i<num.length();i++){
                String k = num.substring(i,i+1);
                if(k.equals("4") || k.equals("7")) count += 1;
            }

            if(count == 0) isLucky = false;
            while (count > 0){
                int a = count % 10;
                if(a == 4 || a== 7){
                    count /=10;
                    continue;
                }
                else{
                    isLucky = false;
                    break;
                }
            }

            if(isLucky) System.out.println("YES");
            else System.out.println("NO");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
