/* nag_quicksort (m01csc) Example Program.
 *
 * Copyright 1990 Numerical Algorithms Group.
 *
 * Mark 2 revised, 1992.
 * Mark 7 revised, 2001.
 * Mark 8 revised, 2004.
 *
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nag_stddef.h>
#include <nagm01.h>

#ifdef __cplusplus
extern "C" {
#endif
static Integer NAG_CALL compare(const Nag_Pointer a, const Nag_Pointer b)
{
  double x = *((const double *) a);
  double y = *((const double *) b);
  return(x < y?-1:(x == y?0:1));
}
#ifdef __cplusplus
}
#endif

#define VEC(I, J) vec[(I) *tdvec + J]
int main(void)
{
  Integer  exit_status = 0, i, j, k, m, n, tdvec;
  double   *vec = 0;
  NagError fail;

  INIT_FAIL(fail);

  /* Skip heading in data file */
  scanf("%*[^\n]");
  printf("nag_quicksort (m01csc) Example Program Results\n");
  scanf("%ld", &m);
  scanf("%ld", &n);
  scanf("%ld", &k);
  if (m >= 1 && n >= 1 && k >= 1)
    {
      if (!(vec = NAG_ALLOC(m*n, double)))
        {
          printf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
      tdvec = n;
    }
  else
    {
      printf("Invalid m or n or k.\n");
      exit_status = 1;
      return exit_status;
    }
  for (i = 0; i < m; ++i)
    for (j = 0; j < n; ++j)
      scanf("%lf", &VEC(i, j));
  /* nag_quicksort (m01csc).
   * Quicksort of set of values of arbitrary data type
   */
  nag_quicksort((Pointer) &VEC(0, k-1), (size_t) m, sizeof(double),
                (ptrdiff_t)(sizeof(double)*n), compare, Nag_Ascending, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_quicksort (m01csc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  printf("\nMatrix with column %ld sorted \n", k);
  for (i = 0; i < m; ++i)
    {
      for (j = 0; j < n; ++j)
        printf(" %8.1f ", VEC(i, j));
      printf("\n");
    }

 END:
  if (vec) NAG_FREE(vec);

  return exit_status;
}