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

#define MESSAGESIZE 4
#define SEND 1
#define RECV 0

char messagebuffer[MESSAGESIZE];

int main(int argc, char** argv)
{

	int token = 0;

	int pipe1_2[2];
	int pipe2_3[2];
	int pipe3_1[2];

       if(argc!=2)
       {
         printf("\nInsufficient Arguments. Exiting...\n\n");
         exit(EXIT_FAILURE);
       }

	pipe(pipe1_2);
	pipe(pipe2_3);
	pipe(pipe3_1);

	if(fork()!=0)
	{ //PROCESS #1

  	  token = atoi(argv[1]);

  	  while(1)
         {

	    close(pipe1_2[RECV]);
	    write(pipe1_2[SEND], &token, MESSAGESIZE);
//           printf("\n[P1] Inserted %d into P1_2", token);fflush(stdout);

	    close(pipe3_1[SEND]);
	    read(pipe3_1[RECV], &token, MESSAGESIZE);
//         printf("\n[P1] Received %d from P3_1", token);fflush(stdout);
	    printf("\n[P1] Current lap: %d", token);fflush(stdout);

	    sleep(1);
           token++;
         }

	}
	else if(fork()!=0)
	{ // PROCESS #2

  	  while(1)
         {
           close(pipe1_2[SEND]);
  	    read(pipe1_2[RECV], &token, MESSAGESIZE);
//           printf("\n[P2] Received %d from P1_2", token);fflush(stdout);

	    close(pipe2_3[RECV]);
	    write(pipe2_3[SEND], &token, MESSAGESIZE);
//         printf("\n[P2] Inserted %d into P2_3", token);fflush(stdout);

	  }

	}
	else
	{//PROCESS #3
  	  while(1)
         {
           close(pipe2_3[SEND]);
	    read(pipe2_3[RECV], &token, MESSAGESIZE);
//         printf("\n[P3] Received %d from P2_3", token);fflush(stdout);

	    close(pipe3_1[RECV]);
	    write(pipe3_1[SEND], &token, MESSAGESIZE);
//         printf("\n[P3] Inserted %d into P3_1", token);fflush(stdout);
	 }
	}
}