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.Arrays;
import java.util.StringTokenizer;
import java.util.stream.IntStream;

public class happyNum {
    private void solve() {

        String str = nextToken();
        int sum = 0;
        for (int i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            int num = Integer.parseInt(String.valueOf(ch));
            if (num == 4 || num == 7) {
                sum++;
            }
        }
        System.out.println((sum == 4 || sum == 7) ? "YES" : "NO");


    }


    public static void main(String[] args) {
        new happyNum().run();
    }

    private BufferedReader reader;
    private StringTokenizer tokenizer;
    private PrintWriter writer;

    private void run() {
        try (BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
             PrintWriter writer = new PrintWriter(new OutputStreamWriter(System.out))) {
            this.reader = reader;
            this.writer = writer;
            this.tokenizer = null;
            solve();
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }
    }


    private int nextInt(int radix) {
        return Integer.parseInt(nextToken(), radix);
    }

    private int nextInt() {
        return Integer.parseInt(nextToken());
    }

    private long nextLong(int radix) {
        return Long.parseLong(nextToken(), radix);
    }

    private long nextLong() {
        return Long.parseLong(nextToken());
    }

    private double nextDouble() {
        return Double.parseDouble(nextToken());
    }

    private int[] nextArr(int size) {
        return Arrays.stream(new int[size]).map(c -> nextInt()).toArray();
    }

    private long[] nextArrL(int size) {
        return Arrays.stream(new long[size]).map(c -> nextLong()).toArray();
    }

    private double[] nextArrD(int size) {
        return Arrays.stream(new double[size]).map(c -> nextDouble()).toArray();
    }

    private char[][] nextCharMatrix(int n) {
        return IntStream.range(0, n).mapToObj(i -> nextToken().toCharArray()).toArray(char[][]::new);
    }

    private int[][] nextIntMatrix(final int n, final int m) {
        return IntStream.range(0, n).mapToObj(i -> nextArr(m)).toArray(int[][]::new);
    }

    private double[][] nextDoubleMatrix(final int n, final int m) {
        return IntStream.range(0, n).mapToObj(i -> nextArrD(m)).toArray(double[][]::new);
    }

    private String nextToken() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    private void printf(String format, Object... args) {
        writer.printf(format, args);
    }

    private void print(Object o) {
        writer.print(o);
    }

    private void println() {
        writer.println();
    }

    private void println(Object o) {
        print(o);
        println();
    }

    private void flush() {
        writer.flush();
    }
}
