快速排序(二)

/**
 * 參考:http://caterpillar.onlyfun.net/Gossip/AlgorithmGossip/QuickSort3.htm
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2006</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */
public class QuickSort1 {
  public static void swap(int[] number, int i, int j) { //交換number數組索引i,j處的值
    int tmp;
    tmp = number[i];
    number[i] = number[j];
    number[j] = tmp;
  }
  public static void sort(int[] number,int left,int right){
    if(left < right){
      int p  = partition(number,left,right);
      sort(number,left,p-1);
      sort(number,p+1,right);
    }
  }
  public static int partition(int[] number, int left, int right) {
    int i = left - 1;
    int s = number[right];
    int tmp;
    for ( int j = left; j < right ; j++) {
      if (number[j] <= s){
        swap(number, ++i, j);
      }
    }
    swap(number, ++i, right);
    return i;
  }

  public static void print(int[] number) { //打印輸入數組內容
    for (int i = 0; i < number.length; i++) {
      System.out.print(number[i] + ",");
    }
    System.out.println("");
  }

  public static void main(String[] args) {
    int[] number = {
        2, 8, 7, 1, 3, 5, 6, 4};
    sort(number, 0, number.length - 1);

    print(number);
  }
}