排序算法

一、选择排序

package org.shydow.structure.sort;

/**
 * @author Rainbow
 * @date 2021/11/29 21:43
 * @desc 时间复杂度：O(n^2)
 */
public class CodeSelectSort {

    public static void SelectionSort(int[] arr) {
        if (null == arr || arr.length < 2) {
            return;
        }
        for (int i = 0; i < arr.length - 1; i++) {
            int minIndex = i;
            for (int j = i + 1; j < arr.length; j++) {
                if (arr[minIndex] > arr[j]) {
                    minIndex = j;
                }
            }
            Swap(arr, i, minIndex);
        }
    }

    private static void Swap(int[] arr, int i, int j) {
        int tmp = arr[i];
        arr[i] = arr[j];
        arr[j] = tmp;
    }
}

二、冒泡排序

package org.shydow.structure.sort;

/**
 * @author Rainbow
 * @date 2021/11/30 7:58
 * @desc 时间复杂度O(n^2)
 */
public class CodeBubbleSort {

    public static void bubbleSort(int[] arr) {
        if (null == arr || arr.length < 2) {
            return;
        }
        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 tmp = arr[j];
                    arr[j] = arr[j + 1];
                    arr[j + 1] = tmp;
                }
            }
        }
    }

}