/*
 * Desempate para N threads.
 */
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define N 5

volatile int s = 0; /* Variável compartilhada */
volatile int interesse[N] = {-1, -1, -1, -1, -1}; 
volatile int ultimo[N-1];

volatile int c = 0;

void* f_thread(void *v) {
  int thr_id = *(int*)v;
  int f,k,i;

  for (i = 0; i < 30; i++) {
    for (f = 0; f < N-1; f++) {
      interesse[thr_id] = f;
      ultimo[f] = thr_id; 
      for (k = 0; k < N && ultimo[f] == thr_id; k++)
	if (k != thr_id)
	  while (f <= interesse[k] && ultimo[f] == thr_id);  
    }
  
    c++;
    s = thr_id;
    printf("Thread %d, s = %d, c = %d.\n", thr_id, s, c); 
    
    interesse[thr_id] = -1;
    sleep(1);
  }
  return NULL;
}

int main() {

  pthread_t thr[N];
  int id[N], i;

  for (i = 0; i < N; i++) {
    id[i] = i;
    pthread_create(&thr[i], NULL, f_thread, &id[i]);
  }

  for (i = 0; i < N; i++) 
    pthread_join(thr[i], NULL); 

  return 0;
}