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".
#                               #
    # author : samars_diary #
    # 07-09-2020 │ 13:56:15 #
#                               #

import sys, os.path

if(os.path.exists('input.txt')):
    sys.stdin = open('input.txt',"r")
    sys.stdout = open('output.txt',"w")

sys.setrecursionlimit(10 ** 5)

def i(): return sys.stdin.readline().strip()
def ii(): return int(sys.stdin.readline())
def li(): return list(sys.stdin.readline().strip())
def mii(): return map(int, sys.stdin.readline().split())
def lii(): return list(map(int, sys.stdin.readline().strip().split()))

print=sys.stdout.write

def solve():
    count=0
    a=li()
    for i in range(len(a)):
        if a[i]=='4' or a[i]=='7':
            count+=1
    if count in [4,7,44,47,74,77]:
        print('YES')
    else:
        print('NO')
solve()