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".
''' *****************************************************************
    *                   BISMILLAHIR RAHMANIR RAHIM                  *
    *                                                               *
    *   Md. Rezwanul Haque                                          *
    *   CSE-2K14 (KUET)                                             *
    *   Gmail : r.haque.249.rh@gmail.com                            *
    *****************************************************************


   ********     *************    *************   **               **             ***              ***          **
   **********   ************      ***********    **               **            ** **             ****         **
   **      **   **                        **     **               **           **   **            ** **        **
   **      **   **                       **      **               **          **     **           **  **       **
   **      **   **                      **       **      ***      **         **       **          **   **      **
   *********    ***********            **        **     ** **     **        *************         **    **     **
   ********     ***********           **         **    **   **    **       ***************        **     **    **
   ****         **                   **          **   **     **   **      **             **       **      **   **
   **  **       **                  **           **  **       **  **     **               **      **       **  **
   **   **      **                 **            ** **         ** **    **                 **     **        ** **
   **    **     ***********       ***********    ****           ****   **                   **    **         ****
   **     **    *************    *************   ***             ***  **                     **   **          ***  '''

n = input()
cnt = 0
for i in range(len(n)):
    if n[i]=='4' or n[i] == '7':
        cnt+=1
        
if cnt == 4 or cnt == 7:
    print("YES")
else:
    print("NO")
