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 X, a, b, c, d;
scanf ("%d", &X);
a= X/1000;
b= (X -a *1000)/100;
c= (X -a *1000 -b *100)/10;
d= X -a *1000 -b *100 -c*10;
if ( (a==2) && (b==2) &&(c==2) &&(d==2) ) {
printf ("4");
}
else if ( (a==2) && (b==2) && (c==2) ) {
printf("3");
}
else if ( (a==2) && (b==2) &&(d==2)  ) {
printf("3");
}
else if ( (a==2) && (c==2) &&(d==2)  ) {
printf("3");
}
else if ( (d==2) && (b==2) &&(c==2)  ) {
printf("3");
}
else if ( (a==2) && (c==2) ) {
printf("2");
}
else if ( (a==2) && (d==2) ) {
printf("2");
}
else if ( (c==2) && (b==2) ) {
printf("2");
}
else if ( (d==2) && (b==2) ) {
printf("2");
}
else if ( (c==2) && (d==2) ) {
printf("2");
}
else if(a == 2){
printf("1");
}
else if ( b== 2){
printf("1");
}
else if( c== 2){
printf("1");
}
else if( d== 2){
printf("1");
}
else{
printf("0");
}
return 0;
}