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 C (Clang 3.8.0) (judge verdict: Accepted)

#include <stdio.h>

int main()
{
	int N;
	scanf("%d",&N);
	int ans=0;
	if(N/1000==2){
		ans += 1;
	}
	N %= 1000;
	if(N/100==2){
		ans++;
	}
	N %= 100;
	if(N/10==2){
		ans++;
	}
	N %= 10;
	if(N==2){
		ans++;
	} 
	printf("%d",ans);
	return 0;
}