text: /* ------------------------------------------------------------------------
   *
   * geqo_ox1.cpp
   *
   *	 order crossover [OX] routines;
   *	 OX1 operator according to Davis
   *	 (Proc Int'l Joint Conf on AI)
   *
   * IDENTIFICATION
   * src/gausskernel/optimizer/geqo/geqo_ox1.cpp
   *
   * -------------------------------------------------------------------------
   */
  /* contributed by:
     =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
     *  Martin Utesch				 * Institute of Automatic Control	   *
     =							 = University of Mining and Technology =
     *  utesch@aut.tu-freiberg.de  * Freiberg, Germany				   *
     =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
   */
  /* the ox algorithm is adopted from Genitor : */
  /*************************************************************/
  /* 															 */
  /* 	Copyright (c) 1990										 */
  /* 	Darrell L. Whitley										 */
  /* 	Computer Science Department								 */
  /* 	Colorado State University								 */
  /* 															 */
  /* 	Permission is hereby granted to copy all or any part of  */
  /* 	this program for free distribution.   The author's name  */
  /* 	and this copyright notice must be included in any copy.  */
  /* 															 */
  /*************************************************************/
  
  #include "postgres.h"
  #include "knl/knl_variable.h"
  #include "optimizer/geqo_random.h"
  #include "optimizer/geqo_recombination.h"
  
  /* ox1
   *
   *	 position crossover
   */
  void ox1(PlannerInfo* root, Gene* tour1, Gene* tour2, Gene* offspring, int num_gene, City* city_table)
  {
      int left, right, k, p, temp;
  
      /* initialize city table */
      for (k = 1; k <= num_gene; k++)
          city_table[k].used = 0;
  
      /* select portion to copy from tour1 */
      left = geqo_randint(root, num_gene - 1, 0);
      right = geqo_randint(root, num_gene - 1, 0);
      if (left > right) {
          temp = left;
          left = right;
          right = temp;
      }
  
      /* copy portion from tour1 to offspring */
      for (k = left; k <= right; k++) {
          offspring[k] = tour1[k];
          city_table[(int)tour1[k]].used = 1;
      }
  
      k = (right + 1) % num_gene; /* index into offspring */
      p = k;                      /* index into tour2 */
  
      /* copy stuff from tour2 to offspring */
      while (k != left) {
          if (!city_table[(int)tour2[p]].used) {
              offspring[k] = tour2[p];
              k = (k + 1) % num_gene;
              city_table[(int)tour2[p]].used = 1;
          }
          p = (p + 1) % num_gene; /* increment tour2-index */
      }
  }
  