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: Wrong Answer)

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
int main(void){
    double i,n,p,ans=0;
    scanf("%lf %lf",&n,&p);
    if(n==1)ans=p;
    else if(n>=40 || n>=p)ans=1;
    else for(i=1; i<=1000000; i++){
        if(fmod(p,pow(i,n))==0)ans=i;
    }
    printf("%.0lf",ans);
    return 0;
}