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.*;
import java.util.*;

/**
 *
 * This Thing was created and developed by Homich
 */
public class Main {
    
    StreamTokenizer in;
    PrintWriter out;
    
    public static void main(String[] args) throws Exception {
        new Main().run();
    }
    
    public void run() throws Exception {
        in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
        out = new PrintWriter(new OutputStreamWriter(System.out));
        solve();
        out.flush();
    }
    
    int nextInt() throws Exception {
        in.nextToken();
        return (int) in.nval;
    }
    
    long nextLong() throws Exception {
        in.nextToken();
        return (long) in.nval;
    }
    
    double nextDouble() throws Exception {
        in.nextToken();
        return in.nval;
    }
    
    String next() throws Exception {
        in.nextToken();
        return in.sval;
    }
    
    public void solve() throws Exception {
       in.ordinaryChars('0', '9');
        in.wordChars('0', '9');
        String s=next();
        int k=0;
        for(int i=0;i<s.length();i++){
        if ((s.charAt(i)=='4')||(s.charAt(i) =='7'))k++;
        if (k>7)break;
        }
        out.println((k==4||k==7)?"YES":"NO");
    }//End Solve
}