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 (GCC 5.4.1) (judge verdict: Accepted)

#include<stdio.h>
int main(){
    int a,b,c,d,e,f,g,cnt=0;
    scanf("%d",&a);
    b=a/1000;
    c=a%100;
    d=c/10;
    e=a%1000;
    f=e/100;
    g=c%10;

    if(b==2){
        cnt++;
    }
    if(d==2){
        cnt++;
    }
    if(f==2){
        cnt++;
    }
    if(g==2){
        cnt++;
    }
    printf("%d\n",cnt);
    return 0;
}