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(void){
    int N,count;
    int Ax,Bx;
    int A,B,C,D;
    
    scanf("%d",&N);
    
    count = 0;
    A = N/1000;
    Ax = N%1000;
    B = Ax/100;
    Bx = Ax%100;
    C = Bx/10;
    D = Bx%10;
    
    if(A == 2) count++;
    if(B == 2) count++;
    if(C == 2) count++;
    if(D == 2) count++;
    
    printf("%d",count);
    
}