#include <stdio.h>

#define T 1
#define F 0
#define MAXSIZE 10		//要排序陣列個數的最大值

typedef struct
{
	int r[MAXSIZE + 1];	//儲存要排序陣列，r[0]用作哨兵或臨時變數
	int length;
}SqList;

void swap(SqList *L, int i, int j)
{
	int temp = L->r[i];
	L->r[i] = L->r[j];
	L->r[j] = temp;
}

//交換順序表L中子表的記錄，使樞軸記錄到位，並返回其所在位置
//此時在它之前（後）的記錄均不大（小）於它
int partition(SqList *L, int low, int high)
{
	int pivotkey;
	pivotkey = L->r[low];					//用子表的第一個記錄作樞軸記錄
	while (low < high)						//從表的兩端交替向中間掃描
	{
		while (low < high && L->r[high] >= pivotkey)
			high--;
		swap(L, low, high);					//將樞軸記錄小的記錄交換到低端
		while (low < high && L->r[low] <= pivotkey)
			low++;
		swap(L, low, high);					//將比樞軸記錄大的記錄交換到高階
	}
	return low;								//返回樞軸所在位置
}

void QSort(SqList *L, int low, int high)
{
	int pivot;
	if (low < high)
	{
		pivot = partition(L, low, high);	//將L->r[low..high]一分為二
											//算出樞軸值pivot
		QSort(L, low, pivot-1);				//對低子表遞迴排序
		QSort(L, pivot+1, high);			//對高子表遞迴排序
	}
}

void quickSort(SqList *L)	//對順序表L作快速排序
{
	QSort(L, 1, L->length);
}

int main()
{
	int i;
	SqList L;
	L.length = 10;
	for (i = 1; i < L.length+1; i++)
	{
		L.r[i] = i;
	}
	L.r[5] = 100;
	L.r[7] = 90;
	for (i = 1; i < L.length+1; i++)
	{
		printf("%d ", L.r[i]);
	}		
	quickSort(&L);
	printf("\n");
	for (i = 1; i < L.length+1; i++)
	{
		printf("%d ", L.r[i]);
	}
	printf("\n");
	return 0;
}
 

執行結果：

陣列表示：

#include <stdio.h>

void swap(int a[], int i, int j)
{
	int temp = a[i];
	a[i] = a[j];
	a[j] = temp;
}

int partition(int a[], int low, int high)
{
	int pivotkey;
	pivotkey = a[low];//單純的記錄值
	while (low < high)//以pivoekey為交換媒介（樞軸），將大於它的放在後邊，小於它的放在前面
	{
		while (low < high && a[high] >= pivotkey)//條件判斷 low < high
			high--;
		swap(a, low, high);
		while (low < high && a[low] <= pivotkey)
			low++;
		swap(a, low, high);
	}
	return low;//返回樞軸所在位置
}

void QSort(int a[], int low, int high)
{
	int pivot;
	if (low < high)//是 if 
	{
		pivot = partition(a, low, high);//將a[]一分為二

		QSort(a, low, pivot - 1);//對低子表遞迴排序
		QSort(a, pivot + 1, high);//對高子表遞迴排序
	}
}

void quickSort(int a[], int low, int high)
{
	QSort(a, low, high);
}

int main()
{
	int i;
	int a[] = {1,2,5,7,9,6,4,2,6,1};
	quickSort(a, 0, 9);
	for (i = 0; i < 10; i++)
	{
		printf("%d ", a[i]);
	}
	printf("\n");
	return 0;
}