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".
lis = [4, 7, 44, 47, 74, 77, 444, 447, 474, 477, 744, 747, 774, 777, 4444, 4447, 4474, 4477, 4744, 4747, 4777, 7444]
#count = 0
#n = int(input())
#for i in lis:
#    if n%i==0:
        
#        count += 1
#        break

#if count ==1:
#    print('YES')
#else:
#    print('NO')

#s = '4774'
#for i in s:
#    print(i)
#lis = []
count = 0
num = 0
n = int(input())
#for i in range(n):
#    c = 0
#    for num in str(i):
#        if num == '4' or num == '7':
#            c += 1
#    if c == len(str(i)):
#        lis.append(i)
#print(lis)

for i in str(n):
    if i == '4' or i =='7':
        num += 1

for j in lis:
    if j == num:
        count = 1
        break
if count == 1:
    print('YES')
else:
    print('NO')