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.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;
//import java.util.*;

public class Main implements Runnable {

    Scanner in = new Scanner(System.in);
    PrintWriter out = new PrintWriter(System.out);
     
    String a;
    int counter=0;
    
    public static void main(String[] args) {
        new Thread(new Main()).start();
    }

    private void read() {
        
        a=in.nextLine();
        
        
    }

    private void solve() {

    	for(int i=0;i<a.length();i++)
    	{
    		if(a.charAt(i)=='7'||a.charAt(i)=='4')
    			counter++;
    	}
    	
    }

    private void write() {

    	if(counter==7||counter==4)
    		out.print("YES");
    	else 
    		out.print("NO");
    }

    @Override
    public void run() {
        read();
        solve();
        write();
        in.close();
        out.flush();
        out.close();
    }
}
