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".
# -*- coding: utf-8 -*-
import sys

w = sys.stdout.write
read = sys.stdin.readline
reads = sys.stdin.read

def r(f=None):
    if f:
        return map(f, read().split())
    else:
        return read().split()

def rs(t,f=None):
    result = []
    result_append = result.append
    for i in xrange(t):
        if f:
            result_append(map(f, read().split()))
        else:
            result_append(read().split())
    return result


####################################################
import math
s = read()

s = s.replace('0', '').replace('1', '').replace('2', '').replace('3', '').replace('5', '').replace('6', '').replace('8', '').replace('9', '').replace('\n', '')
s = str(len(s))
s = s.replace('4', '').replace('7', '')
if s=='':
    w('YES')
else:
    w('NO')
