#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <unistd.h>

#include <omp.h>

#define MAX 33 //41
int Fibonacci(int n)
{   int x, y;
    if (n < 2)
        return n;
    else {
        x = Fibonacci(n - 1);
        y = Fibonacci(n - 2);
        return (x + y);
}    }
int FibonacciTask(int n)
{   int x, y;
    if (n < 2)
        return n;
    else {
#pragma omp task shared(x)
        x = Fibonacci(n - 1);
#pragma omp task shared(y)
        y = Fibonacci(n - 2);
#pragma omp taskwait
        return (x + y);
 }    }

int main(int argc, char * argv[])
{int FibNumber[MAX] = {0};
  struct timeval time_start, time_end;
  int i = 0;
  // openmp related print message
  printf("CPU_ONLN= %ld\n", sysconf(_SC_NPROCESSORS_ONLN));
  printf("Number of CPUs=%d\n", omp_get_num_procs());
  printf("Number of max threads=%d\n", omp_get_max_threads());
  printf("Number of executing thread=%d\n", omp_get_thread_num());
  printf("Number of threads=%d\n", omp_get_num_threads());
  omp_set_num_threads( omp_get_num_procs()  );
  gettimeofday(&time_start, NULL);
#pragma omp parallel
    {
#pragma omp single private(i)
        for(i = 1; i < MAX; i++) {
            FibNumber[i] = FibonacciTask(i);
    }    }
   gettimeofday(&time_end, NULL);
   time_end.tv_usec = time_end.tv_usec-time_start.tv_usec;
   time_end.tv_sec = time_end.tv_sec-time_start.tv_sec;
   time_end.tv_usec += (time_end.tv_sec*1000000);
   printf("Execution time of The Fibonacci Numbers with OpenMP : %lf sec\n", time_end.tv_usec / 1000000.0);
   for(i = 0; i < MAX; i++)
       printf("%d ", FibNumber[i]);
   printf("\n-------------------------------\n");
   return 0;
}