快排的递归和非递归实现

//快排的递归
void quickSort1(int* root,int low,int high)
{
	int pat=root[low];
	if(low<high)
	{
		int i=low,j=high;
		while(i<j)
		{	
			while(i<j&&root[j]>pat)
				j--;
			root[i]=root[j];


			while(i<j&&root[i]<pat)
				i++;
			root[j]=root[i];

		}
		root[i]=pat;
		quickSort1(root,low,i-1);
		quickSort1(root,i+1,high);
	}
	
}

//快排的非递归
int partion(int* root,int low,int high)
{
	int part=root[low];
	while(low<high)
	{
		while(low<high&&root[high]>part) high--;
		root[low]=root[high];
		while(low<high&&root[low]<part) low++;
		root[high]=root[low];
	}
	root[low]=part;
	return low;
}

void quickSort2(int* root,int low,int high)
{
	stack<int> st;
	int k;
	if(low<high)
	{
		st.push(low);
		st.push(high);
		while(!st.empty())
		{
			int j=st.top();st.pop();
			int i=st.top();st.pop();

			k=partion(root,i,j);

			if(i<k-1)
			{
				st.push(i);
				st.push(k-1);
			}
			if(k+1<j)
			{
				st.push(k+1);
				st.push(j);
			}
		}

	}
	
}

int main()
{
	int a[8]={4,2,6,7,9,5,1,3};
	quickSort1(a,0,7);
	//quickSort2(a,0,7);
	int i;
	for(i=0;i<8;i++)
		cout<<a[i]<<"	";
	cout<<endl;
	getchar();
	return 0;
}