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 a {
    /*
     * In a Programming contest, you are expected to print the output at the
     * end, so `output` variable will hold all the processed results till the
     * end
     */
    public static String output = "";

    // Program's starting point
    public static void main(String[] args) {

        /*
         * A Scanner class slows down Input/Output a LOT ,thereby increasing
         * your code execution time , Hence for best results that is Fast I/O
         * try to use BufferedReader
         */
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        /*
         * Generally Code Chef, Hacker Rank gives X number of test cases so we
         * process the input for each.
         */

        try {
            String s = br.readLine();
            /*
             * Logic of the program must be separated from the meta code to
             * increase readability and help debugging easier
             * Also note that Solver object is created inside for loop to
             * avoid multiple object creation that drastically increases
             * execution time and memory usage
             */
            Solver solver = new Solver();
            solver.solve(s);

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // Print the final output
        System.out.println(output);
    }
}

class Solver {

    /*
     * Logic goes here ...
     * Add to the global variables after processing the input
     * Maybe reverse a string or parse to an integer or , etc.
     */
    public void solve(String s) {
        int luckyDigits = 0;

        for(int i = 0; i < s.length(); ++i) {
            char c = s.charAt(i);
            if(c == '4' || c == '7') {
                ++luckyDigits;
            }

        }

        if(luckyDigits == 4 || luckyDigits == 7) {
            a.output = a.output.concat("YES");
        } else {
            a.output = a.output.concat("NO");
        }

    }

}

