//
// Written for Computer Networks and Systems lab classes
// AUTHOR : Sergiusz Warga

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <sys/wait.h>

int child_task(int a, int b) {
    return a + b;
}

int main() {
    srandom(time(NULL));
    int a = random() % 11;
    int b = random() % 11 + 20;
    int sum = 0;

    pid_t pid;

    pid = fork();

    if (pid == -1) {    // If something went wrong.
        perror("Fork: ");
        exit(EXIT_FAILURE);
    }

    if (pid == 0) {     // If this is a child process.
        sum = child_task(a, b);
        exit(sum);
    }

    wait(&sum);
    while (!(WIFEXITED(sum)));
    printf("%d\n", WEXITSTATUS(sum));
    return 0;
}