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".
#!/usr/bin/env python2
# -*- coding: utf-8 -*-
import sys
input = sys.stdin
output = sys.stdout

def digits(n,base=10):
    if n<0:
        n = -n
    D = []
    while True:
        n,m = divmod(n,base)
        D.append(m)
        if n==0:
            break
    return D

def solve(n):
    HD = [d for d in digits(n) if d in [4,7]]
    LD = digits(len(HD))
    if all(d in [4,7] for d in LD):
        return 'YES'
    else:
        return 'NO' 

n = int(input.readline())

a = solve(n)
output.write('%s\n' % a)
