/*
* Jalview - A Sequence Alignment Editor and Viewer
* Copyright (C) 2005 AM Waterhouse, J Procter, G Barton, M Clamp, S Searle
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
*/

package MCview;

import java.util.*;

public class Zsort {

  public static void Zsort(Vector bonds) {

    sort(bonds,0,bonds.size()-1);
  }



  public static void sort(Vector bonds,int p, int r) {
    int q;

    if (p < r) {
      q = partition(bonds,p,r);
      sort(bonds,p,q);
      sort(bonds,q+1,r);
    }
  }

  private static int partition(Vector bonds, int p, int r) {
    float x = ((Bond)bonds.elementAt(p)).start[2];
    int i = p-1;
    int j = r+1;

    while(true) {
      do {
        j = j-1;
      }	while (j >= 0  && ((Bond)bonds.elementAt(j)).start[2] > x);

      do {
        i = i+1;
      } while (i < bonds.size() && ((Bond)bonds.elementAt(i)).start[2] < x);

      if ( i < j) {
        Bond tmp = (Bond)bonds.elementAt(i);
        bonds.setElementAt(bonds.elementAt(j),i);
        bonds.setElementAt(tmp,j);
      } else {
        return j;
      }
    }
  }
}