8种排序算法的总结(java代码)

1.冒泡排序

package com.sort;

public class BubbleSort {

    public void BubbleSort(int[] a){

        for (int i =0; i < a.length - 1;i++){
            for (int j = 0; j < a.length-1-i ;j++){
            if (a[j] > a[j+1]){
//                swap(a[j],a[j+1]);
                int temp = a[j];
                a[j] = a[j+1];
                a[j+1] = temp;
            }
            }
        }
    }
    private void swap(int x, int y) {
        int temp = x;
        x = y;
        y = temp;
    }
    public static void println(int[] a){
        System.out.print("[");
        for (int i = 0; i < a.length;i++){
            System.out.print(a[i]);
        }
        System.out.print("]" + "\n");
    }
    public static void main(String[] args){
        int[] a ={2,3,1,5,6,7,4,3,7,};
        BubbleSort bs = new BubbleSort();
        System.out.println("排序前的数组是：");
        println(a);
        bs.BubbleSort(a);
        System.out.println("排序后的数组是：");
        println(a);
    }
}

2. 选择排序

package com.sort;

public class SelectSort {
    public void SelectSort(int [] array){
        for(int i = 0; i < array.length-1;i++){
            for(int j = i+1; j< array.length;j++){
                if(array[i]>array[j]){
//                    swap(array[i],array[j]);
                    int temp = array[i];
                    array[i] = array[j];
                    array[j] = temp;
                }
            }
        }
    }

    private void swap(int i, int j) {
        int temp = i;
        i = j;
        j = temp;
    }
    public static void println(int[] a){
        System.out.print("[");
        for (int i = 0; i < a.length;i++){
            System.out.print(a[i]);
        }
        System.out.print("]" + "\n");
    }
    public static void main(String[] args) {
        int[] a = {2, 3, 1, 5, 6, 7, 4, 3, 7,};
        SelectSort ss = new SelectSort();
        System.out.println("排序前的数组是：");
        println(a);
        ss.SelectSort(a);
        System.out.println("排序后的数组是：");
        println(a);
    }
}

3.插入排序

package com.sort;

public class InsertSort {
    public void InsertSort(int [] arr){
        for(int i= 1; i< arr.length;i++){
                    if(arr[i]<arr[i-1]){
                        int temp = arr[i];
                        int k = i-1;
                        for(int j = k;j>=0 && temp < arr[j];j--){
                            arr[j+1]= arr[j];
                            k--;
                        }
                        arr[k+1]=temp;
                    }

        }
    }
    public static void println(int[] array) {
        for (int i = 0; i < array.length; i++) {
            System.out.print(+array[i]);
            if (i != array.length - 1) {
                System.out.print(",");
            }
        }
        System.out.print("\n");
    }
    public static void main(String[] args) {
        int[] a = {2, 3, 1, 5, 6, 7, 4, 3, 7,};
        InsertSort ss = new InsertSort();
        System.out.println("排序前的数组是：");
        println(a);
        ss.InsertSort(a);
        System.out.println("排序后的数组是：");
        println(a);
    }
}

4.归并排序

package com.sort;

public class MergeSort {
    //　private　static　long　sum　=　0;

    /**
     * 　*　<pre>
     * 　*　二路归并
     * 　*　原理：将两个有序表合并和一个有序表
     * 　*　</pre>
     * 　*
     * 　*　@param　a
     * 　*　@param　s
     * 　*　第一个有序表的起始下标
     * 　*　@param　m
     * 　*　第二个有序表的起始下标
     * 　*　@param　t
     * 　*　第二个有序表的结束小标
     * 　*
     */
    private static void merge(int[] a, int s, int m, int t) {
        int[] tmp = new int[t - s + 1];
        int i = s, j = m, k = 0;
        while (i < m && j <= t) {
            if (a[i] <= a[j]) {
                tmp[k] = a[i];
                k++;
                i++;
            } else {
                tmp[k] = a[j];
                j++;
                k++;
            }
        }
        while (i < m) {
            tmp[k] = a[i];
            i++;
            k++;
        }
        while (j <= t) {
            tmp[k] = a[j];
            j++;
            k++;
        }
        System.arraycopy(tmp, 0, a, s, tmp.length);
    }

    /**
     * 　*
     * 　*　@param　a
     * 　*　@param　s
     * 　*　@param　len
     * 　*　每次归并的有序集合的长度
     */
    public static void mergeSort(int[] a, int s, int len) {
        int size = a.length;
        int mid = size / (len << 1);
        int c = size & ((len << 1) - 1);
        //　-------归并到只剩一个有序集合的时候结束算法-------//
        if (mid == 0)
            return;
        //　------进行一趟归并排序-------//
        for (int i = 0; i < mid; ++i) {
            s = i * 2 * len;
            merge(a, s, s + len, (len << 1) + s - 1);
        }
        //　-------将剩下的数和倒数一个有序集合归并-------//
        if (c != 0)
            merge(a, size - c - 2 * len, size - c, size - 1);
        //　-------递归执行下一趟归并排序------//
        mergeSort(a, 0, 2 * len);
    }

    public static void main(String[] args) {
        int[] a = new int[]{4, 3, 6, 1, 2, 5};
        mergeSort(a, 0, 1);
        for (int i = 0; i < a.length; ++i) {
            System.out.print(a[i] + "　");
        }
    }
}

5.快速排序

package com.sort;

public class QuickSort {
    public int part(int [ ] a, int low, int high){
        int key = a[low];
        while(low < high){
            while(low< high && a[high]>key )
                high--;
                a[low]=a[high];
            while(low< high && a[low]>key )
                low++;
            a[high]=a[low];

        }
        a[low]=key;
        return low;

    }
    public void  QuickSort(int[] a,int low, int high){

            if (low<high){
                int index = part(a, low, high);
                QuickSort(a,low,index-1);
                QuickSort(a,index+1,high);
}

    }
    public static void println(int[] array) {
        for (int i = 0; i < array.length; i++) {
            System.out.print(+array[i]);
            if (i != array.length - 1) {
                System.out.print(",");
            }
        }
        System.out.print("\n");
    }
    public static void main(String[] args) {
        int[] a = {2, 3, 1, 5, 6, 7, 4, 3, 7,};
        QuickSort ss = new QuickSort();
        System.out.println("排序前的数组是：");
        println(a);
        ss.QuickSort(a,0, a.length - 1);
        System.out.println("排序后的数组是：");
        println(a);
    }
}

6.希尔排序

package com.sort;

import java.util.Arrays;

public class ShellSort{
    public static void ShellSort(int[] data) {
        int j = 0;
        int temp = 0;
        for (int increment = data.length / 2; increment > 0; increment /= 2) {
            System.out.println("increment（步长）:" + increment);
            for (int i = increment; i < data.length; i++) {
                // System.out.println("i:" + i);
                temp = data[i];
                for (j = i - increment; j >= 0; j -= increment) {
                    // System.out.println("j:" + j);
                    // System.out.println("temp:" + temp);
                    // System.out.println("data[" + j + "]:" + data[j]);
                    if (temp < data[j]) {
                        data[j + increment] = data[j];
                    } else {
                        break;
                    }
                }
                data[j + increment] = temp;
            }
            for (int i = 0; i < data.length; i++)
                System.out.print(data[i] + " ");
        }
    }

    public static void main(String[] args) {
        int[] data = new int[] { 26, 53, 67, 48, 57, 13, 48, 32, 60, 50 };
        ShellSort(data);
        System.out.println(Arrays.toString(data));
    }
        }

7.基数排序

package com.sort;

public class RadixSort {
    public static void sort(int[] number, int d) //d表示最大的数有多少位
    {
        int k = 0;
        int n = 1;
        int m = 1; //控制键值排序依据在哪一位
        int[][]temp = new int[10][number.length]; //数组的第一维表示可能的余数0-9
        int[]order = new int[10]; //数组orderp[i]用来表示该位是i的数的个数
        while(m <= d)
        {
            for(int i = 0; i < number.length; i++)
            {
                int lsd = ((number[i] / n) % 10);
                temp[lsd][order[lsd]] = number[i];
                order[lsd]++;
            }
            for(int i = 0; i < 10; i++)
            {
                if(order[i] != 0)
                    for(int j = 0; j < order[i]; j++)
                    {
                        number[k] = temp[i][j];
                        k++;
                    }
                order[i] = 0;
            }
            n *= 10;
            k = 0;
            m++;
        }
    }
    public static void main(String[] args)
    {
        int[]data =
                {73, 22, 93, 43, 55, 14, 28, 65, 39, 81, 33, 100};
        RadixSort.sort(data, 3);
        for(int i = 0; i < data.length; i++)
        {
            System.out.print(data[i] + "\n");
        }
    }
}

8.堆排序

package com.sort;

import java.util.Arrays;

public class HeapSort {
    /**
     * 构建大根堆
     */
    public static void adjustHeap(int[] a, int i, int len) {
        int temp, j;
        temp = a[i];
        for (j = 2 * i; j < len; j *= 2) {// 沿关键字较大的孩子结点向下筛选
            if (j < len && a[j] < a[j + 1])
                ++j; // j为关键字中较大记录的下标
            if (temp >= a[j])
                break;
            a[i] = a[j];
            i = j;
        }
        a[i] = temp;
    }

    public static void heapSort(int[] a) {
        int i;
        for (i = a.length / 2 - 1; i >= 0; i--) {// 构建一个大顶堆
            adjustHeap(a, i, a.length - 1);
        }
        for (i = a.length - 1; i >= 0; i--) {// 将堆顶记录和当前未经排序子序列的最后一个记录交换
            int temp = a[0];
            a[0] = a[i];
            a[i] = temp;
            adjustHeap(a, 0, i - 1);// 将a中前i-1个记录重新调整为大顶堆
        }
    }

    public static void main(String[] args) {
        int a[] = { 51, 46, 20, 18, 65, 97, 82, 30, 77, 50 };
        heapSort(a);
        System.out.println(Arrays.toString(a));
    }
}

以上代码亲测成功。。。