#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <math.h>

/* Include polybench common header. */
#include <polybench.h>

/* Include benchmark-specific header. */
/* Default data type is double, default size is 20x1000. */
#include "jacobi-2d-imper.h"

/* Array initialization. */
static void init_array(int n,
                       DATA_TYPE POLYBENCH_2D(A, N, N, n, n),
                       DATA_TYPE POLYBENCH_2D(B, N, N, n, n))
{
  int i, j;

  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++)
    {
      A[i][j] = ((DATA_TYPE)i * (j + 2) + 2) / n;
      B[i][j] = ((DATA_TYPE)i * (j + 3) + 3) / n;
    }
}

/* DCE code. Must scan the entire live-out data.
   Can be used also to check the correctness of the output. */
static void print_array(int n,
                        DATA_TYPE POLYBENCH_2D(A, N, N, n, n))

{
  int i, j;

  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++)
    {
      fprintf(stderr, DATA_PRINTF_MODIFIER, A[i][j]);
      if ((i * n + j) % 20 == 0)
        fprintf(stderr, "\n");
    }
  fprintf(stderr, "\n");
}

/* Main computational kernel. The whole function will be timed,
   including the call and return. */
static void kernel_jacobi_2d_imper(int tsteps,
                                   int n,
                                   DATA_TYPE POLYBENCH_2D(A, N, N, n, n),
                                   DATA_TYPE POLYBENCH_2D(B, N, N, n, n))
{
  int t, i, j;

  for (t = 0; t < _PB_TSTEPS; t++)
  {
    for (i = 1; i < _PB_N - 1; i++)
      for (j = 1; j < _PB_N - 1; j++)
        B[i][j] = 0.2 * (A[i][j] + A[i][j - 1] + A[i][1 + j] + A[1 + i][j] + A[i - 1][j]);
    for (i = 1; i < _PB_N - 1; i++)
      for (j = 1; j < _PB_N - 1; j++)
        A[i][j] = B[i][j];
  }
}

int main(int argc, char **argv)
{
  /* Retrieve problem size. */
  int n = N;
  int tsteps = TSTEPS;

  /* Variable declaration/allocation. */
  POLYBENCH_2D_ARRAY_DECL(A, DATA_TYPE, N, N, n, n);
  POLYBENCH_2D_ARRAY_DECL(B, DATA_TYPE, N, N, n, n);

  /* Initialize array(s). */
  init_array(n, POLYBENCH_ARRAY(A), POLYBENCH_ARRAY(B));

  /* Start timer. */
  polybench_start_instruments;

  /* Run kernel. */
  kernel_jacobi_2d_imper(tsteps, n, POLYBENCH_ARRAY(A), POLYBENCH_ARRAY(B));

  /* Stop and print timer. */
  polybench_stop_instruments;
  polybench_print_instruments;

  /* Prevent dead-code elimination. All live-out data must be printed
     by the function call in argument. */
  polybench_prevent_dce(print_array(n, POLYBENCH_ARRAY(A)));

  /* Be clean. */
  POLYBENCH_FREE_ARRAY(A);
  POLYBENCH_FREE_ARRAY(B);

  return 0;
}