快速排序的递归与非递归实现

import java.util.Arrays;import java.util.Stack;class QuickSort {public static void quickSort(int[] array){if (array==null||array.length==0){return;}//递归算法//quickSortCore(array,0,array.length-1);//非递归quickSortCore2(array,0,array.length-1);}public static void quickSortCore(int[] array, int p, int r){if (p<r){int q=partition(array, p,r);quickSortCore(array,p,q-1);quickSortCore(array,q+1,r);}}public static int partition(int[] array, int p, int r){int x=array[r];int i=p;int j=i;while (i<r){if(array[i]<x){swap(array,i,j);j++;}i++;}swap(array,r,j);return j;}public static void swap(int[] array, int i,int j){int temp=array[i];array[i]=array[j];array[j]=temp;}//非递归，用循环？用栈记录？记录什么？记录当前划分序列的下标起始点public static void quickSortCore2(int[] array, int start, int end){Stack<Integer> stack=new Stack<Integer>();stack.push(start);stack.push(end);while (!stack.empty()){//后进先出int r=stack.pop();int p=stack.pop();//划分的终止条件if (p>=r){continue;}int q=partition(array,p,r);stack.push(p);stack.push(q-1);stack.push(q+1);stack.push(r);}}public static void main(String[] args) {int[] array={2,5,8,4,7,3,6};quickSort(array);System.out.println(Arrays.toString(array));}}