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 Java8 (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.*;


public class Main {
    public static void main(String args[]){
            Scanner sc = new Scanner(System.in);
            
            int n = sc.nextInt();
            int count = 0;
            while(n != 0){
                if (n % 10  == 2) {
                    count++;
                    n /= 10;
                }
            }
            System.out.println(count);

            sc.close();
        }
    
}