八大排序汇总
作者：互联网
八大排序汇总
摘要：在详细的学习完八大排序之后，我们就要进行反复的练习了，我打算每天都写一遍，这样天天练习必然熟能生巧，还能练习打字速度，在这里我先来一次八大排序的代码汇编，以便有需要时直接查阅参考。
目录1.冒泡排序
public static void bubbleSort(int[] arr) {// 冒泡排序
for (int i = 0; i < arr.length; i++) {
for (int j = 0; j < arr.length - 1; j++) {
if (arr[j] > arr[j + 1]) {
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
}
2.选择排序
public static void selectionSort(int[] arr) {//选择排序
for (int i = 0; i < arr.length - 1; i++) {
int minIndex = i;
int min = arr[i];
for (int j = i + 1; j < arr.length; j++) {
if (min > arr[j]) {
minIndex = j;
min = arr[j];
}
}
arr[minIndex] = arr[i];
arr[i] = min;
}
}
3.插入排序
public static void insertSort(int[] arr) {//插入排序
for (int i = 1; i < arr.length; i++) {
for (int j = i - 1; j >= 0; j--) {
if (arr[j] > arr[j + 1]) {
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
} else {
break;
}
}
}
}
4.希尔排序
public static void shellSort(int[] arr) {//希尔排序
for (int gap = arr.length / 2; gap > 0; gap /= 2) {
for (int i = gap; i < arr.length; i += gap) {
for (int j = i - gap; j >= 0; j -= gap) {
if (arr[j] > arr[j + gap]) {
int temp = arr[j];
arr[j] = arr[j + gap];
arr[j + gap] = temp;
} else {
break;
}
}
}
}
}
5.基数排序
public static void ridix(int[] arr) {//基数排序
int max = arr[0];
for (int i = 1; i < arr.length; i++) {
if (max < arr[i])
max = arr[i];
}
int maxSize = (max + "").length();
for (int i = 1, n = 1; i <= maxSize; i++, n *= 10) {
int[][] bucket = new int[10][arr.length];
int[] bucketElement = new int[10];
for (int j = 0; j < arr.length; j++) {
int element = arr[j] / n % 10;
bucket[element][bucketElement[element]] = arr[j];
bucketElement[element]++;
}
for (int x = 0, index = 0; x < bucketElement.length; x++) {
if (bucketElement[x] != 0) {
for (int z = 0; z < bucketElement[x]; z++) {
arr[index] = bucket[x][z];
index++;
}
}
bucketElement[x] = 0;
}
}
System.out.println(Arrays.toString(arr));
}
6.快速排序
public static void quickSort(int arr[], int left, int right) {//快速排序
if (left >= right) {
return;
}
int i = left;
int j = right;
int base = arr[i];
while (i != j) {
while (i < j && arr[j] >= base) {
j--;
}
while (i < j && arr[i] <= base) {
i++;
}
int temp = arr[j];
arr[j] = arr[i];
arr[i] = temp;
}
arr[left] = arr[i];
arr[i] = base;
quickSort(arr, left, i - 1);
quickSort(arr, i + 1, right);
}
7.归并排序
public static void emergeSort(int[] arr, int left, int right) {//归并排序
if (left >= right) {
return;
}
int mid = (left + right) / 2;
emergeSort(arr, left, mid);
emergeSort(arr, mid + 1, right);
emerge(arr, left, mid, right);
}
public static void emerge(int[] arr, int left, int mid, int right) {
int trv1 = left;
int trv2 = mid + 1;
int[] tempArr = new int[right - left + 1];
int tempTrv = 0;
while (trv1 <= mid && trv2 <= right) {
if (arr[trv1] < arr[trv2]) {
tempArr[tempTrv++] = arr[trv1++];
} else {
tempArr[tempTrv++] = arr[trv2++];
}
}
while (trv1 <= mid) {
tempArr[tempTrv++] = arr[trv1++];
}
while (trv2 <= right) {
tempArr[tempTrv++] = arr[trv2++];
}
for (int i = 0; i < tempArr.length; i++) {
arr[left + i] = tempArr[i];
}
}
8.堆排序
public static void heapSort(int[] arr) {//堆排序
for (int i = arr.length - 1; i >= 0; i--) {
heapAdjest(arr, i, arr.length);
}
for (int i = 1; i < arr.length; i++) {
int temp = arr[0];
arr[0] = arr[arr.length - i];
arr[arr.length - i] = temp;
heapAdjest(arr, 0, arr.length - i);
}
}
public static void heapAdjest(int[] arr, int parent, int length) {
int child = parent * 2 + 1;
int temp = arr[parent];
while (child < length) {
if (child + 1 < length && arr[child] < arr[child + 1]) {
child++;
}
if (temp >= arr[child]) {
break;
}
arr[parent] = arr[child];
parent = child;
child = parent * 2 + 1;
}
arr[parent] = temp;
}
标签：arr,八大,temp,int,汇总,length,排序,left 来源： https://www.cnblogs.com/B307-NCAI/p/16170969.html