在Java中,对数据进行排序可以通过多种方法实现,以下是一些常用的排序方法:
使用`Arrays.sort()`方法
int[] array = {4, 2, 8, 1, 6};
Arrays.sort(array);
使用`Collections.sort()`方法
List
list = new ArrayList<>(); list.add(4);
list.add(2);
list.add(8);
list.add(1);
list.add(6);
Collections.sort(list);
自定义`Comparator`对象
List
list = new ArrayList<>(); list.add("apple");
list.add("banana");
list.add("cherry");
list.sort(Comparator.naturalOrder());
常用排序算法
快速排序:
public static Integer[] sort(Integer[] nums, int low, int high) {
if (low < high) {
int pi = partition(nums, low, high);
sort(nums, low, pi - 1);
sort(nums, pi + 1, high);
}
return nums;
}
冒泡排序:
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]) {
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
}
选择排序:
public static void selectionSort(int[] arr) {
int n = arr.length;
for (int i = 0; i < n - 1; i++) {
int min_idx = i;
for (int j = i + 1; j < n; j++)
if (arr[j] < arr[min_idx])
min_idx = j;
int temp = arr[min_idx];
arr[min_idx] = arr[i];
arr[i] = temp;
}
}
插入排序:
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;
}
}
希尔排序
public static void shellSort(int[] arr) {
int n = arr.length;
for (int gap = n / 2; gap > 0; gap /= 2) {
for (int i = gap; i < n; i++) {
int temp = arr[i];
int j;
for (j = i; j >= gap && arr[j - gap] > temp; j -= gap)
arr[j] = arr[j - gap];
arr[j] = temp;
}
}
}