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 sorting(masukan):
    tmp = []
    for i in masukan :
        tmp += [int(i)]
    tmp.sort()
    return(tmp)

def persingkat(tmp):
    total = 0
    for j in range(len(tmp)):
        if(j < len(tmp)-1):
            if tmp[j]!=tmp[j+1]:
                total += ord(str(tmp[j]))
        else:
            total += ord(str(tmp[j]))
    return(total)

masukan = input()
data = "47"
lucky = ord("4")+ord("7")
total = 0
for i in masukan:
    for j in data:
        if(i==j):
            total += 1
var = persingkat(sorting(str(total)))
if( var == ord("4") or var == ord("7") or var == lucky):
    print("YES")
else:
    print("NO")

