Excercise 2.1.1

#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <sys/unistd.h>
int divBy2 (int* arr,int size)
{
    int cnt = 0;
    for (int i=0; i<size; i++)
    {
        if (arr[i] % 2 == 0) ++cnt;
    }
    return cnt;
}
int divBy3 (int* arr,int size)
{
    int cnt = 0;
    for (int i=0; i<size; i++)
    {
        if (arr[i] % 3 == 0) ++cnt;
    }
    return cnt;
}
int main(int argc, char **argv)
{
    int arr[1000];
    memset(arr, 0, sizeof(arr));
    freopen("number.txt", "r", stdin);
    int curr = -999;
    scanf("%d", &curr);
    int size = 0;
    while (curr != -999)
    {
        arr[size] = curr;
        curr = -999;
        ++size;
        scanf("%d", &curr);
    }
    if (fork() == 0) printf("%d\n",divBy2(arr,size));
    else {
        wait(NULL);
        printf("%d\n",divBy3(arr,size));
    }
}