Java八大排序算法

Java八大排序算法：

package sort;import java.util.ArrayList;import java.util.Arrays;import java.util.List;/** * mysort *  * @author Arya * */public class MySort {public static void main(String[] args) {MySort mySort = new MySort();mySort.insertSort();mySort.shellSort();mySort.selectSort();mySort.bubbleSort();mySort.quickSort();mySort.HeapSort();mySort.mergingSort();mySort.radixSort();}/** * 直接插入排序：稳定 时间复杂度：最好O(n),其它O(n^2) 空间复杂度：O(1) */public void insertSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };int temp = 0;for (int i = 1; i < a.length; ++i) {temp = a[i];int j = i - 1;for (; j >= 0 && temp < a[j]; --j) {a[j + 1] = a[j];}a[j + 1] = temp;}for (int i = 0; i < a.length; ++i)System.out.print(a[i] + "--");System.out.println();}/** * 希尔排序：不稳定 时间复杂度：O(nlog2n)～O(n^2) 空间复杂度：O(1) */public void shellSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };int d = a.length;int temp = 0;while (true) {d = (int) Math.ceil(d / 2);for (int x = 0; x < d; x++) {for (int i = x + d; i < a.length; i += d) {int j = i - d;temp = a[i];for (; j >= 0 && temp < a[j]; j -= d) {a[j + d] = a[j];}a[j + d] = temp;}}if (d == 1)break;}for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}/** * 选择排序：不稳定 时间复杂度：O(n^2) 空间复杂度：O(1) */public void selectSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };int position = 0;for (int i = 0; i < a.length; i++) {int j = i + 1;position = i;int temp = a[i];for (; j < a.length; j++) {if (a[j] < temp) {temp = a[j];position = j;}}a[position] = a[i];a[i] = temp;}for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}/** * 冒泡排序：稳定 时间复杂度：最好O(n),其它O(n^2) 空间复杂度：O(1) */public void bubbleSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };int temp = 0;int flag = 1;for (int i = 0; i < a.length - 1 && flag == 1; i++) {flag = 0;for (int j = 0; j < a.length - 1 - i; j++) {if (a[j] > a[j + 1]) {temp = a[j];a[j] = a[j + 1];a[j + 1] = temp;flag = 1;}}}for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}/** * 快速排序：不稳定 时间复杂度：最好，平均O(nlog2n),最差O(n^2) 空间复杂度：O(log2n) */public void quickSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };_quickSort(a, 0, a.length - 1);for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}public void _quickSort(int[] list, int low, int high) {if (low < high) {int middle = getMiddle(list, low, high);_quickSort(list, low, middle - 1);_quickSort(list, middle + 1, high);}}public int getMiddle(int[] list, int low, int high) {int tmp = list[low];while (low < high) {while (low < high && list[high] >= tmp) {high--;}list[low] = list[high];while (low < high && list[low] <= tmp) {low++;}list[high] = list[low];}list[low] = tmp;return low;}/** * 堆排序：不稳定 时间复杂度：O(nlog2n) 空间复杂度：O(1) */public void HeapSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };int n = a.length;int i;int temp;InitCreateHeap(a, n);for (i = n - 1; i > 0; i--) {temp = a[0];a[0] = a[i];a[i] = temp;CreateHeap(a, i, 0);}for (i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}public void InitCreateHeap(int a[], int n) {for (int i = (n - 1) / 2; i >= 0; i--)CreateHeap(a, n, i);}public void CreateHeap(int a[], int n, int h) {int i, j, flag;int temp;i = h;j = 2 * i + 1;flag = 0;temp = a[i];while (j < n && flag != 1) {if (j < n - 1 && a[j] < a[j + 1])j++;if (temp > a[j])flag = 1;else {a[i] = a[j];i = j;j = 2 * i + 1;}}a[i] = temp;}/** * 归并排序：稳定 时间复杂度：O(nlog2n) 空间复杂度：O(n) */public void mergingSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };sort(a, 0, a.length - 1);for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}public void sort(int[] data, int left, int right) {// TODO Auto-generated method stubif (left < right) {// 找出中间索引int center = (left + right) / 2;// 对左边数组进行递归sort(data, left, center);// 对右边数组进行递归sort(data, center + 1, right);// 合并merge(data, left, center, right);}}public void merge(int[] data, int left, int center, int right) {// TODO Auto-generated method stubint[] tmpArr = new int[data.length];int mid = center + 1;// third记录中间数组的索引int third = left;int tmp = left;while (left <= center && mid <= right) {// 从两个数组中取出最小的放入中间数组if (data[left] <= data[mid]) {tmpArr[third++] = data[left++];} else {tmpArr[third++] = data[mid++];}}// 剩余部分依次放入中间数组while (mid <= right) {tmpArr[third++] = data[mid++];}while (left <= center) {tmpArr[third++] = data[left++];}// 将中间数组中的内容复制回原数组while (tmp <= right) {data[tmp] = tmpArr[tmp++];}// System.out.println(Arrays.toString(data));}/** * 基数排序：稳定 时间复杂度：O(kn)，其中n是排序元素个数，k是数字位数。 空间复杂度：O(kn) */public void radixSort() {int a[] = { 49, 38, 65, 97, 76, 13, 27, 49, 78, 34, 12, 64, 5, 4, 62,99, 98, 54, 56, 17, 18, 23, 34, 15, 35, 25, 53, 51 };sort(a);for (int i = 0; i < a.length; i++)System.out.print(a[i] + "--");System.out.println();}public void sort(int[] array) {// 首先确定排序的趟数;int max = array[0];for (int i = 1; i < array.length; i++) {if (array[i] > max) {max = array[i];}}int time = 0;// 判断位数;while (max > 0) {max /= 10;time++;}// 建立10个队列;List<ArrayList> queue = new ArrayList<ArrayList>();for (int i = 0; i < 10; i++) {ArrayList<Integer> queue1 = new ArrayList<Integer>();queue.add(queue1);}// 进行time次分配和收集;for (int i = 0; i < time; i++) {// 分配数组元素;for (int j = 0; j < array.length; j++) {// 得到数字的第time+1位数;int x = array[j] % (int) Math.pow(10, i + 1)/ (int) Math.pow(10, i);ArrayList<Integer> queue2 = queue.get(x);queue2.add(array[j]);queue.set(x, queue2);}int count = 0;// 元素计数器;// 收集队列元素;for (int k = 0; k < 10; k++) {while (queue.get(k).size() > 0) {ArrayList<Integer> queue3 = queue.get(k);array[count] = queue3.get(0);queue3.remove(0);count++;}}}}}