在Java中实现排序,你可以选择多种算法,包括冒泡排序、插入排序、选择排序、快速排序和归并排序等。下面是一些常见排序算法的Java实现示例:
冒泡排序(Bubble Sort)
public class BubbleSort {
public static void bubbleSort(int[] arr) {
int n = arr.length;
for (int i = 0; i < n - 1; i++) {
for (int j = 0; j < n - i - 1; j++) {
if (arr[j] > arr[j + 1]) {
// 交换arr[j]和arr[j+1]
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
}
public static void main(String[] args) {
int[] arr = {64, 34, 25, 12, 22, 11, 90};
bubbleSort(arr);
System.out.println("排序后的数组:");
for (int i = 0; i < arr.length; i++) {
System.out.print(arr[i] + " ");
}
}
}
插入排序(Insertion Sort)
public class InsertionSort {
public static void insertionSort(int[] arr) {
int n = arr.length;
for (int i = 1; i < n; ++i) {
int key = arr[i];
int j = i - 1;
while (j >= 0 && arr[j] > key) {
arr[j + 1] = arr[j];
j = j - 1;
}
arr[j + 1] = key;
}
}
public static void main(String[] args) {
int[] arr = {64, 34, 25, 12, 22, 11, 90};
insertionSort(arr);
System.out.println("排序后的数组:");
for (int i = 0; i < arr.length; i++) {
System.out.print(arr[i] + " ");
}
}
}
选择排序(Selection Sort)
public class SelectionSort {
public static void selectionSort(int[] arr) {
int n = arr.length;
for (int i = 0; i < n - 1; i++) {
int minIndex = i;
for (int j = i + 1; j < n; j++) {
if (arr[j] < arr[minIndex]) {
minIndex = j;
}
}
// 交换最小值和当前位置的元素
int temp = arr[minIndex];
arr[minIndex] = arr[i];
arr[i] = temp;
}
}
public static void main(String[] args) {
int[] arr = {64, 25, 12, 22, 11};
selectionSort(arr);
System.out.println("排序后的数组:");
for (int i = 0; i < arr.length; i++) {
System.out.print(arr[i] + " ");
}
}
}
快速排序(Quick Sort)