Java实现冒泡排序，选择排序，插入排序

/**
 * 两种冒泡排序的性能比较
 */
public class DubbleSort {
    private static boolean checkArray(int[] data){
        if(data == null || data.length == 0){
            return false;
        }
        return true;
    }
    
    public static int[] dubbleSort(int[] data){
        if(!checkArray(data)){
            return null;
        }
        int temp;
        int runNum = 0;
        for (int i = 0; i < data.length; i++) {
            System.out.println(String.format("i=%d", i));
            for (int j = i; j < data.length; j++) {
                System.out.print(String.format("j=%d,", j));
                if(data[i] > data[j]){
                    temp = data[i];
                    data[i] =data[j];
                    data[j] = temp;
                }
                runNum++;
            }
            System.out.println("");
        }
        System.out.println(String.format("dubbleSort运行次数 ： %d", runNum));
        return data;
    }
    
    public static int[] dubbleSort1(int[] data){
        if(!checkArray(data)){
            return null;
        }
        System.out.println(String.format("int数组长度：%d", data.length));
        int temp;
        int runNum = 0;
        for (int i = 0; i < data.length-1; i++) {
            System.out.println(String.format("i=%d", i));
            for (int j = 0; j < data.length-1-i; j++) {
                System.out.print(String.format("j=%d,", j));
                if(data[j] > data[j+1]){
                    temp = data[j];
                    data[j] =data[j+1];
                    data[j+1] = temp;
                }
                runNum++;
            }
            System.out.println("");
        }
        System.out.println(String.format("dubbleSort运行次数 ： %d", runNum));
        return data;
    }
    
    public static void main(String[] args) {
        int[] data = new int[]{8,4,9,13,11,99,2,1,5,3,6};;
        dubbleSort(data);
        for (int i : data) {
            System.out.print(i+",");
        }
        System.out.println("");
        int[] data1 = new int[]{8,4,9,13,11,99,2,1,5,3,6};
        dubbleSort1(data1);
        for (int i : data1) {
            System.out.print(i+",");
        }
    }
}

选择排序：

思想：首先找到数组中最小的那个元素，其次，将它和第一个元素交换。接下来找第二小和第二个交换。运行时间和输入无关，数据移动最少

特点：数据移动最少，不稳定，适合排序数较少时使用

package cn.guangboyuan;

import java.util.Arrays;

/**
 * @author Red Ants
 *         微信公众号：程序员之路
 * 选择排序
 */
public class SelectionSort {
    
    public static int[] selectionSort(int[] ints){
        int temp;
        int runNum = 0;
        for (int i = 0; i < ints.length; i++) {
            for (int j = i+1; j < ints.length; j++) {
                if(ints[j]<ints[i]){
                    temp = ints[i];
                    ints[i] = ints[j];
                    ints[j] = temp;
                }
                runNum++;
            }
        }
        System.out.println(String.format("运行次数：%d", runNum));
        return  ints;
    }
    
    public static void main(String[] args) {
        int[] ints = new int[]{8,4,9,13,11,99,2,1,5,3,6};
        selectionSort(ints);
        System.out.println(Arrays.toString(ints));
    }
}

插入排序：

思想：首先数组前两个数比较排序，然后第三个数和前两个数进行排序以此类推

特点：稳定，适合大部分已排序时较好

package cn.guangboyuan;

import java.util.Arrays;

/**
 * @author Red Ants
 *         微信公众号：程序员之路
 * 插入排序
 */
public class InsertionSort {
    
    public static int[] insertionSort(int[] ints) {
        int target = 0;
        int runNum = 0;
        for (int i = 1; i < ints.length; i++) {
            int j = i;
            target = ints[i];
            while (j > 0 && target < ints[j-1]) {
                ints[j] = ints[j-1];
                j--;
                runNum++;
            }
            ints[j] = target;
        }
        System.out.println(String.format("运行次数：%d", runNum));
        return ints;
    }
    
    public static void main(String[] args) {
        int[] ints = new int[]{8,4,9,13,11,99,2,1,5,3,6};
        System.out.println(Arrays.toString(insertionSort(ints)));
    }
}