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".
# import re
x=int(input())
# temp=0

# for i in range(len(x)):
#     if x[i]=='4' or x[i]=='7':
#         temp+=1
# if temp==4 or temp==7:
#     print("YES")
# else:
#     print("No")

# text=re.sub(r'7','-',x)
# text=re.sub(r'4','-',text)
#
# temp='-'*len(x)
# if text==temp:
#     print("YES")
# else:
#     print("NO")
# dict={}
#
# for i in range(len(x)):
#     if x[i] in dict:
#         temp=dict[x[i]]
#         dict[x[i]]=temp+1
#     else:
#         dict[x[i]]=1
# # print(list(dict.keys()))
# # print(dict)
# if dict[7]:
#     print("YES")
# else:
#     print("NO")
temp=0
while(x):
    if x%10==7 or x%10==4:
        temp+=1
    x=x//10
if temp==7 or temp==4:
    print("YES")
else:
    print("NO")