#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main() {
	pid_t pids[3];
	int i;
	for (i=0; i<3; ++i) {
		fflush(stdout);
		pids[i]=fork();
		if (pids[i]==-1) {
			perror("fork");
			exit(EXIT_FAILURE);
		}
		if (pids[i]==0) {
			// child
			printf("child  %d %d %d\n", i, getppid(), getpid());
		}
		else {
			// parent
			printf("parent %d %d %d\n", i, getppid(), getpid());
			waitpid(pids[i], NULL, 0);
		}
	}
	return EXIT_SUCCESS;
}