// from cilkplus.org
//
// compile with (gcc 4.9 plus; tested with 5.3.1)
//	gcc -fcilkplus -lcilkrts -o parfib parfib.c

#include <cilk/cilk.h>
#include <cilk/cilk_api.h>
#include <stdio.h>
#include <stdlib.h>

long int fib(int n)
{
    if (n < 2)
        return n;
    long int x = cilk_spawn fib(n-1);
    long int y = fib(n-2);
    cilk_sync;
    return x + y;
}

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

  int n = atoi(argv[1]);
  char *workerstr = argv[2];
  
  if (workerstr)
    __cilkrts_set_param("nworkers",workerstr);
    

  printf("fib(%d) = %d\n", n, fib(n));
  
}