快排与希尔排序

#include<iostream>
#include<cmath>
#include<vector>
#include<string>
#include<stdlib.h>
#include<algorithm>
using namespace std;
const int N = 100;
void quick_sort(int q[], int l, int r)
{
	if (l >= r)
		return;

	int x = q[(r+l)/2];
	int i = l - 1, j = r + 1;

	while (i < j)
	{
		do i++;  while (q[i] < x);
		do j--;  while (q[j] > x);
		if (i < j)
			swap(q[i], q[j]);
	}
	quick_sort(q, l, j),
		quick_sort(q, j + 1, r);
	return;
}
void ShellSort(int* arr, int len)
{
	int temp, gap = len / 2;
	while (gap > 0)
	{
		for (int i = 0; i < gap; i++)
		{
			for (int j = i + gap; j < len; j += gap)
			{
				int temp = arr[j];
				int k;
				for (k = j - gap; k >= 0 && temp < arr[k]; k -= gap)
				{
					arr[k + gap] = arr[k];
				}
				arr[k + gap] = temp;
			}
		}
		gap /= 2;
	}
}
int main()
{
	int q[N];
	int len;
	cout << "数组的长度是:" << endl;
	cin >> len;
	cout << "输入数组的元素:" << endl;
	for (int i = 0; i < len; i++)
	{
		cin >> q[i];
	}
	int choose;
	cout << "选0展示希尔排序结果,选1展示快排结果:" << endl;
	cin >> choose;
	switch (choose)
	{
	case 0:
		ShellSort(q, len);
		cout << "希尔排序如下:" << endl;
		for (int i = 0; i < len; i++)
			cout << q[i] << " ";
 		break;
	case 1:
		quick_sort(q, 0, len-1);
		cout << "快排如下:" << endl;
		for (int i = 0; i < len; i++)
			cout << q[i] << " ";
		break;
	}
}