#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
#include <unistd.h>
#include <sys/wait.h>
#include <string.h>
#include <ctype.h>
#include <time.h>


void
output(int i, time_t t) {
    struct tm *timeinfo;
    timeinfo = localtime (&t);
    fflush(stdout);
    printf("  %d  ", i);

    switch (i) {
        case 3:
            printf("S:%d\n", timeinfo->tm_sec);
            break;
        case 2:
            printf("M:%d\n", timeinfo->tm_min);
            break;
        case 1:
            printf("H:%d\n", timeinfo->tm_hour);
            break;
    }

    return ;
}

int
main(void)
{
    int pid, st;
    time_t t = time( NULL);

    int fd[2];
    pipe(fd);
    for (int i = 0; i < 3; i++) {
        pid = fork();
        if (pid != 0) {
            if (i == 0) {
                close(fd[0]);//close for reading
                time_t t = time( NULL);
                write(fd[1], &t, sizeof(t));
                write(fd[1], &t, sizeof(t));
                write(fd[1], &t, sizeof(t));
                while (wait(&st) != -1);
                close(fd[1]);
                return 0;
            } else {
                close(fd[1]);//close for writing
                fflush(stdout);
                time_t t;
                read(fd[0], &t, sizeof(t));
                while (wait(&st) != -1);
                output(i, t);
                close(fd[0]);
                return 0;
            }
        } else if (i < 2){
            continue;
        } else {//правнук
                close(fd[1]);//close for writing
                fflush(stdout);
                time_t t;
                read(fd[0], &t, sizeof(t));
                output(i+1, t);
                close(fd[0]);
                return 0;
        }
    }

    return 0;
}