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

#ifdef _OPENMP
#include <omp.h>
#endif

#ifdef LIKWID_PERFMON
#include <likwid-marker.h>
#else
#define LIKWID_MARKER_INIT
#define LIKWID_MARKER_REGISTER(regionTag)
#define LIKWID_MARKER_START(regionTag)
#define LIKWID_MARKER_STOP(regionTag)
#define LIKWID_MARKER_CLOSE
#endif

int main(int argc, char *argv[]) {
  const int size = 1000;

  double *a = malloc(size * sizeof(double));
  double *b = malloc(size * sizeof(double));

  double *sum  = malloc(size * sizeof(double));
  double *prod = malloc(size * sizeof(double));

  LIKWID_MARKER_INIT;

  #pragma omp parallel
  {
    LIKWID_MARKER_REGISTER("sum");
    LIKWID_MARKER_REGISTER("prod");

    #pragma omp barrier

    #pragma omp for
    for (int i = 0; i < size; i++) {
      a[i] = (double)(i + 1);
      b[i] = a[i];
    }

    LIKWID_MARKER_START("sum");

    #pragma omp for
    for (int i = 0; i < size; i++) {
      sum[i] = a[i] + b[i];
    }

    LIKWID_MARKER_STOP("sum");
    LIKWID_MARKER_START("prod");

    #pragma omp for
    for (int i = 0; i < size; i++) {
      prod[i] = a[i] * b[i];
    }

    LIKWID_MARKER_STOP("prod");
  }

  printf("      Sum: first = %lf - last = %lf\n", sum[0], sum[size-1]);
  printf("  Product: first = %lf - last = %lf\n", prod[0], prod[size-1]);

  LIKWID_MARKER_CLOSE;

  free(a); free(b); free(sum); free(prod);

  return 0;
}