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 Julia (0.5.0) (judge verdict: Runtime Error)

function main()
  
  N = split(chomp(readline()),"")
  
  ans = 0
  
  for in 1:4
    
    if N[i] == "2"
      ans += 1
    end
    
  end
  
end

main()