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".
def lucky():
	Dict = {}
	i = raw_input()
	i = list(i)
	
	for each in range(len(i)):
		Dict[i[each]] = (i.count(i[each]))

	count4 = 0
	count7 = 0
	for j in Dict:
		if j == '4':
			count4 += Dict[j]
		if j == '7':
			count7 += Dict[j]

	if (count4+ count7 == 7 or count4+ count7 == 4): #and count4 > 0 and count7 > 0:# (count7 <= 7 and count7 > 0):
		print "YES"
	else:
		print "NO"

lucky()