非递归的快排

/* 快排的非递归算法 *//* 使用队列的任务分解方法 *//* Key : 队列如何快速实现？ */#include <stdio.h>#include <queue.h>typedef struct _TASK_QSORT {int* list;int low;int high;}QsTask; int Partition(int a[], int low, int high) {int pivot = a[low];while (low < high){while (low < high && a[high] >= pivot) --high;a[low] = a[high];while (low < high && a[low] <= pivot) ++low;a[low] = a[high];}a[low] = pivot;return low;}void QSort(int a[], int low, int high) {int mid = 0;QsTask firstTask,NxtTsk;firstTask.list = a;firstTask.low = low;firstTask.high = high;queue<QsTask> task;task.push(firstTask);while (!task.empty()){firstTask = task.front();mid = Partition(firstTask.list,firstTask.low,firstTask.high);NxtTsk.list = firstTask.list;NxtTsk.low = firstTask.low;NxtTsk.high = mid;task.push(NxtTsk);NxtTsk.low = mid;NxtTsk.high = firstTask.high;task.push(NxtTsk);}}main() {int a[] = {12,98,76,35,22,10};int i=0;QSort(a,0,5);for (i; i < 6; ++i){printf("%d/t",a[i]);}printf("/n");} 

 

老师的堆栈做法 

 

#include "stdio.h"#define N 8int r[N+1] = { 0,49,38,65,97,76,13,27,49 };void QuickSort(int *r, int n){ int i,j,rp,top; struct { int left; int right; } stack[100],x,y; x.left=1; x.right=n; top=1; stack[top]=x; while(top>0) { x=stack[top--]; i=x.left; j=x.right; rp=r[i]; while ( i<j ) { while ( i < j && r[j] >= rp ) j--; r[i] = r[j]; while ( i < j && r[i] <= rp) i++; r[j] = r[i];} r[i] = rp; if ( i < x.right-1) { y.left =i+1; y.right=x.right; stack[++top]=y; } if ( i > x.left+1) { y.right=i-1; y.left =x.left; stack[++top]=y; } }}void main(){ int i; QuickSort(r,8); for(i=1;i<=8;i++) printf("%d ",r[i]); printf("/n");}