Problem:
Score : 100 points

Problem Statement

You are given an integer N that has exactly four digits in base ten.
How many times does 2 occur in the base-ten representation of N?

Constraints

1000 \leq N \leq 9999

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

1222

Sample Output 1

3

2 occurs three times in 1222. By the way, this contest is held on December 22 (JST).

Sample Input 2

3456

Sample Output 2

0

Sample Input 3

9592

Sample Output 3

1

Solution in Python (3.4.3) (judge verdict: Runtime Error)

N = int(input())
H = int(input())
W = int(input())
while 0<N:
    A = int(input())
    B = int(input())
if (H == A and W == B) or (H == A/2 and W == B/2):
    cnt = +1
print(int(cnt))