#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <string.h>
#include <errno.h>

int main() {
    for (int start = 0; start < 50; start += 10) {
        pid_t pid = fork();
        if (pid == -1) {
            fprintf(stderr, "Error forking: %s\n", strerror(errno));
            return 1;
        } else if (pid == 0) {
            // I AM FORK!
            for (int i = start; i < start + 10; i++) {
                printf("%d: %d\n", pid, i);
            }
            printf("Fork %d finished counting from %d\n", getpid(), start);
            return 0;
        } else {
            printf("Fork %d successfull\n", pid);
        }
    }


    fork();
    fork();
    fork();
    printf("Hello World\n");
}