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;

public class LuckyDigits {
    public static char FOUR = '4';
    public static char SEVEN = '7';
    
    public static String YES = "YES";
    public static String NO = "NO";
    
    public String number;
    public int countLucky;
    
    public LuckyDigits(){
        init();
    }
    
    private void init(){
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        try {
            number = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    public void countLuckyDigits(){
        countLucky = 0;
        char[] arr = number.toCharArray();
        for(int i = 0; i < arr.length; i++)
            if((FOUR == arr[i]) || (SEVEN == arr[i]))
                countLucky++;
    }
    
    public void ifLucky(){
        char[] arr = Integer.toString(countLucky).toCharArray();
        for(int i = 0; i < arr.length; i++)
            if((arr[i] != FOUR) && (arr[i] != SEVEN)){
                System.out.print(NO);
                return;
            }
        System.out.print(YES);
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        LuckyDigits ld = new LuckyDigits();
        ld.countLuckyDigits();
        ld.ifLucky();
    }

}
