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".
s=int(input())
ls=[]
ch=0
x=True

while(s>0):
    temp=s%10
    ls.append(temp)
    s//=10

ls.reverse()


for i in range(len(ls)):
    if ((ls[i]==4) or (ls[i]==7)):
        ch+=1

lch=[]
while(ch>0):
    temp=ch%10
    lch.append(temp)
    ch//=10

if lch==[]:
    lch.append(0)
    
lch.reverse()

for j in range(len(lch)):
    if ((lch[j]==4) or (lch[j]==7)):
        x=True
    else:
        x=False

if x==False:
    print ('NO')
else:
    print ('YES')
