快速排序

#include "iostream"
//left,right为数组下标
int partition(int a[],int left,int right)
{
	int i = left;
	int j = right;
	int temp = a[i];
	while (i<j)
	{
		while (i<j && a[j] >= temp)//必须加等号
			j--;
		if (i<j)
			a[i] = a[j];
		while (i<j && a[i] <= temp)//必须加等号
			i++;
		if (i<j)
			a[j] = a[i];
	}
	a[i] = temp;
	return i;
}
void quickSort(int a[],int left,int right)
{
	int dp;
	if (left < right)
	{
		dp = partition(a,left,right);
		quickSort(a,left,dp-1);
		quickSort(a, dp+1,right);
	}
}
int main()
{
	int a[9] = { 8, 2, 6, 12, 1, 9, 5, 5, 10 };
	int i;
	quickSort(a, 0, 8);/*排好序的结果*/
	for (i = 0; i<8; i++)
		printf("%4d", a[i]);
	getchar();
	return 0;                                                                                                                                                                                                                                               
}