【Java】快速排序的非递归实现

	/**
	 * 递归调用
	 */
	public void qSort(int[] a, int low, int high) {
		int pivot;
		if (low >= high)
			return;
		
		//原始递归操作
		// pivot = partition(a, low, high); // 将数列一分为二
		// qSort(a, low, pivot - 1); // 对低子表排序
		// qSort(a, pivot + 1, high); // 对高子表排序

		// 优化递归操作
		while (low 

	/**
	 * 非递归
	 */
	public void qSort2(int[] a, int low, int high) {
		int pivot;
		if (low >= high)
			return;
		Stack stack = new Stack();
		stack.push(low);
		stack.push(high);
		while (!stack.empty()) {
			// 先弹出high,再弹出low
			high = stack.pop();
			low = stack.pop();
			pivot = partition(a, low, high);
			// 先压low,再压high
			if (low 

import java.util.Arrays;
import java.util.Stack;

/**
 * 
 * @Description 快速排序的递归与非递归实现
 *
 * @author yongh
 * @date 2018年9月14日 下午2:39:00
 */
public class QuickSort {
	public void quickSort(int[] a) {
		if (a == null)
			return;
		qSort(a, 0, a.length - 1);
	}
	/**
	 * 递归
	 */
	public void qSort(int[] a, int low, int high) {
		int pivot;
		if (low >= high)
			return;
		
		//原始递归操作
		// pivot = partition(a, low, high); // 将数列一分为二
		// qSort(a, low, pivot - 1); // 对低子表排序
		// qSort(a, pivot + 1, high); // 对高子表排序

		// 优化递归操作
		while (low = high)
			return;
		Stack stack = new Stack();
		stack.push(low);
		stack.push(high);
		while (!stack.empty()) {
			// 先弹出high,再弹出low
			high = stack.pop();
			low = stack.pop();
			pivot = partition(a, low, high);
			// 先压low,再压high
			if (low  a[high])
			swap(a, low, high);
		if (a[(low + high) / 2] > a[high])
			swap(a, (low + high) / 2, high);
		if (a[low] = pivotKey)
				high--;
			a[low] = a[high];
			// swap(a, low, high); //比基准小的元素放到低端
			while (low