数据结构--经典排序算法

算法复杂度：

 

#include<iostream>
#include<stdio.h>
#include<math.h>
using namespace std;
class paixu
{
public:
	void bubbleSort0(int* pData, int length)//1，冒泡排序
	{
		int temp;
		for (int i = 0; i != length; ++i)
		{
			for (int j = 0; j != length; ++j)
			{
				if (pData[i] < pData[j])
				{
					temp = pData[i];
					pData[i] = pData[j];
					pData[j] = temp;
				}
			}
		}
	}
	void selectionSort(int* pData, int length)//2,选择排序
	{
		int minIndex, temp;
		for (int i = 0; i < length - 1; i++)
		{
			minIndex = i;
			for (int j = i + 1; j < length; j++) 
			{
				if (pData[j] <pData[minIndex]) // 寻找最小的数
				{     
					minIndex = j;                 // 将最小数的索引保存
				}
			}
			temp = pData[i];
			pData[i] = pData[minIndex];
			pData[minIndex] = temp;
		}
	}
	void insertionSort(int* pData, int length)//3,插入排序
	{
		int preIndex, current;
		for (int i = 1; i < length; i++) 
		{
			preIndex = i - 1;
			current = pData[i];
			while (preIndex >= 0 && pData[preIndex] > current) 
			{
				pData[preIndex + 1] = pData[preIndex];
				preIndex--;
			}
			pData[preIndex + 1] = current;
		}
	}
	void shellSort(int* pData, int length) //4，希尔排序
	{
		
		for (int gap =floor(length / 2); gap > 0; gap = floor(gap / 2))
		{
			for (int i = gap; i < length; i++) {
				int j = i;
				int current = pData[i];
				while (j - gap >= 0 && current < pData[j - gap]) 
				{
					pData[j] = pData[j - gap];
					j = j - gap;
				}
				pData[j] = current;
			}
		}
	
	}
	int len;
	void heapSort(int* pData, int length)//5，堆排序（Heap Sort）
	{
		buildMaxHeap(pData, length);

		for (int i = length - 1; i > 0; i--)
		{
			swap(pData, 0, i);
			len--;
			heapify(pData, 0);
		}
	}
	void merge_sort(int *data, int start, int end, int *result)//6，归并排序
	{
		if (1 == end - start)//如果区间中只有两个元素，则对这两个元素进行排序
		{
			if (data[start] > data[end])
			{
				int temp = data[start];
				data[start] = data[end];
				data[end] = temp;
			}
			return;
		}
		else if (0 == end - start)//如果只有一个元素，则不用排序
			return;
		else
		{
			//继续划分子区间，分别对左右子区间进行排序
			merge_sort(data, start, (end - start + 1) / 2 + start, result);
			merge_sort(data, (end - start + 1) / 2 + start + 1, end, result);
			//开始归并已经排好序的start到end之间的数据
			merge(data, start, end, result);
			//把排序后的区间数据复制到原始数据中去
			for (int i = start; i <= end; ++i)
				data[i] = result[i];
		}
	}
	void QuickSort(int a[], int start, int end)//7，快速排序
	{
		if (start > end)
		{
			return;
		}

		int i = start;
		int j = end;
		int k = a[i];
		while (i < j)
		{
			while (i < j && a[j] > k)//先从后面开始找小于k的值
				j--;
			a[i] = a[j];//找到小于k的值，替换a[i]
			while (i < j && a[i] < k)//从前面找大于k的值
				i++;
			a[j] = a[i];//找到大于k的值，刚才a[j]的值已经赋刚才的a[i];a[j]的值用现在找到的大于k的值填充
		}
		a[j] = k;//最后i = j; 把k的值赋给a[i];

		QuickSort(a, i + 1, end);
		QuickSort(a, start, i - 1);
	}

private:
	///////////////////////////////(堆排序)
	void buildMaxHeap(int* pData, int length)
	{   // 建立大顶堆
		len = length;
		for (int i = floor(len / 2); i >= 0; i--) 
		{
			heapify(pData, i);
		}
	}

	void heapify(int* pData, int i)
	{     // 堆调整
		int left = 2 * i + 1,
			right = 2 * i + 2,
			largest = i;

		if (left < len && pData[left] >pData[largest]) 
		{
			largest = left;
		}

		if (right < len && pData[right] > pData[largest]) 
		{
			largest = right;
		}

		if (largest != i)
		{
			swap(pData, i, largest);
			heapify(pData, largest);
		}
	}

	void swap(int*pData, int i, int j) 
	{
		int temp = pData[i];
		pData[i] = pData[j];
		pData[j] = temp;
	}
	////////////////////////////////////////////(归并排序)
	void merge(int *data, int start, int end, int*result)
	{
		
		int left_length = (end - start + 1) / 2 + 1;//左部分区间的数据元素的个数
		int left_index = start;
		int right_index = start + left_length;
		int result_index = start;
		while (left_index < start + left_length && right_index < end + 1)
		{
			//对分别已经排好序的左区间和右区间进行合并
			if (data[left_index] <= data[right_index])
				result[result_index++] = data[left_index++];
			else
				result[result_index++] = data[right_index++];
		}
		while (left_index < start + left_length)
			result[result_index++] = data[left_index++];
		while (right_index < end + 1)
			result[result_index++] = data[right_index++];
	}
////////////////////////////////////////////////

};
int main()
{
	int Sqlist[] = { 0, 4, 2, 1, 3 };
	int length = sizeof(Sqlist) / sizeof(int);
	int start = 0;
	int end = length - 1;
	int result[5];
	//paixu().bubbleSort0(Sqlist, length);
	//paixu().selectionSort(Sqlist, length);
	//paixu().insertionSort(Sqlist, length);
	//paixu().shellSort(Sqlist, length);
	//paixu().heapSort(Sqlist, length);
	//paixu().merge_sort(Sqlist, start,end,result);
	paixu().QuickSort(Sqlist, start, end);
	for (int i = 0; i != length; ++i)
	{
		cout << Sqlist[i] << " ";
	}
	cout << endl;
	system("pause");
	return 0;

}