标签：10 arr Java temp int ++ length 排序 left
Arrays排序
public static void arraysSort(int[] arr){
// 数组为null时 如何去判断?
if (arr == null || arr.length<=1) {
System.out.println("arraySort()判断接收到的数组为null");
return ;
}
// Arrays.sort(arr); // 升序 部分升序: 形参为arr,0,3 左闭右开
Integer[] reverseArr = new Integer[arr.length];
for (int i = 0; i < arr.length; i++) {
reverseArr[i] = arr[i];
}
Arrays.sort(reverseArr, Collections.reverseOrder());
for (int i = 0; i < arr.length; i++) {
arr[i] = reverseArr[i];
}
}
0 数组工具类
1 selection sort
public static void selectionSort(int[] arr) {
for (int i = 0; i < arr.length; i++) {
int min = arr[i];
int index = i;
for (int j = i+1; j < arr.length; j++) {
if (min > arr[j]){
min = arr[j];
index = j;
}
}
int temp = arr[i];
arr[i] = min;
arr[index] = temp;
}
}
1 选择排序
2 heap sort
public static void max_heapify(int[] arr, int n) {
int c = 0;
for (int i = (n-1)/2; i >= 0 ; i--) {
c = 2*i + 1;
if (c != n && arr[c] < arr[c+1])
c++;
if (arr[i] < arr[c]){
int temp = arr[c];
arr[c] = arr[i];
arr[i] = temp;
}
}
}
public static void heapSort(int[] arr){
for (int i = arr.length-1; i > 0 ; i--) {
max_heapify(arr, i);
int temp = arr[i];
arr[i] = arr[0];
arr[0] = temp;
}
}
2 堆排序
3 bubble sort
public static void bubbleSort(int[] arr) {
for (int i = 0; i < arr.length-1; i++) {
for (int j = 0; j < arr.length-1-i; j++) {
if (arr[j] > arr[j+1]){
int temp = arr[j+1];
arr[j+1] = arr[j];
arr[j] = temp;
}
}
}
}
3 冒泡排序
4 quick sort
public static void quickSort(int[] arr, int left, int right) {
if (left>right) return ;
int i, j, temp, t;
i = left;
j = right;
temp = arr[left];
while (i != j){
while (arr[j] >= temp && i<j)
j--;
while (arr[i] <= temp && i<j)
i++;
if (i < j){
t = arr[j];
arr[j] = arr[i];
arr[i] = t;
}
}
arr[left] = arr[i];
arr[i] = temp;
quickSort(arr, left, i-1);
quickSort(arr, i+1, right);
}
4 快速排序
5 insertion sort
public static void insertionSort(int[] arr) {
for (int i = 0; i < arr.length; i++) {
for (int j = i; j > 0; j--) {
if (arr[j] < arr[j-1]){
int temp = arr[j-1];
arr[j-1] = arr[j];
arr[j] = temp;
}
}
}
}
5 直接插入排序
6 shell sort
public static void shellSort(int[] arr){
for (int i = arr.length/2; i > 0; i/=2) {
for (int j = i; j < arr.length; j++) {
for (int k = j; k > 0 && k+1 >0 ; k--) {
if (arr[k] < arr[k-1]){
int temp = arr[k-1];
arr[k-1] = arr[k];
arr[k] = temp;
}
}
}
}
}
6 希尔排序
7 merge sort
public static void mergeArr(int[] arr, int left, int mid, int right){
int[] temp = new int[arr.length];
int p1=left, p2=mid+1, k=left;
while (p1<=mid && p2<=right){
if (arr[p1] < arr[p2]) temp[k++] = arr[p1++];
else temp[k++] = arr[p2++];
}
while (p1<=mid) temp[k++] = arr[p1++];
while (p2<=right) temp[k++] = arr[p2++];
for (int i = left; i <= right; i++) {
arr[i] = temp[i];
}
}
public static void mergeSort(int[] arr, int left, int right){
if (left>=right)return;
int mid = (left+right)/2;
mergeSort(arr, left, mid);
mergeSort(arr, mid+1, right);
mergeArr(arr, left, mid, right);
}
7 归并排序
8 bucket sort
public static void bucketSort(int[] arr){
int max = 0;
for (int i = 0; i < arr.length; i++) {
max = arr[i] > max ? arr[i] : max;
}
int[] bucket = new int[max+1];
for (int i = 0; i < arr.length; i++) {
bucket[arr[i]]++;
}
int res = 0;
for (int i = 0; i < bucket.length; i++) {
while (bucket[i]-- > 0)
arr[res++] = i ;
}
}
8 桶排序
9 count sort
public static void countSort(int[] arr, int left, int right) {
int[] bucket = new int[right-left+1];
for (int i = 0; i < arr.length; i++) {
bucket[ arr[i]-left ]++;
}
int res = 0;
for (int i = 0; i < bucket.length; i++) {
while (bucket[i]-- > 0)
arr[res++] = i + left;
}
}
9 计数排序
10 radix sort
public static void radixSort(int[] arr){
int max = 0;
for (int i = 0; i < arr.length; i++) {
max = arr[i] > max ? arr[i] : max;
}
int d = 1;
while (max/10>0){
d++;
max/=10;
}
int[][] bs = new int[10][arr.length];
int base = 10;
for (int i = 0; i < d; i++) {
int[] bLen = new int[10];
for (int j = 0; j < arr.length; j++) {
int w = arr[j] % base / (base/10);
bs[w][bLen[w]] = arr[j];
bLen[w]++;
}
int res = 0;
for (int b = 0; b < bs.length; b++) {
for (int p = 0; p < bLen[b]; p++) {
arr[res++] = bs[b][p];
}
}
}
}
10 基数排序
标签：10,arr,Java,temp,int,++,length,排序,left 来源： https://www.cnblogs.com/H742/p/15419095.html
本站声明： 1. iCode9 技术分享网（下文简称本站）提供的所有内容，仅供技术学习、探讨和分享； 2. 关于本站的所有留言、评论、转载及引用，纯属内容发起人的个人观点，与本站观点和立场无关； 3. 关于本站的所有言论和文字，纯属内容发起人的个人观点，与本站观点和立场无关； 4. 本站文章均是网友提供，不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属；如您发现该文章侵犯了您的权益，可联系我们第一时间进行删除； 5. 本站为非盈利性的个人网站，所有内容不会用来进行牟利，也不会利用任何形式的广告来间接获益，纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。