【数组排序】 -选择排序和冒泡排序

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        int n=input.nextInt();   //输入数组长度

        int a [] = new int[n];
        for (int i=0;i<n;i++){        //为数组赋值
            int x=input.nextInt();
            a[i]=x;
        }
        //排序前，先把内容打印出来
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i] + " ");
        }
        System.out.println(" ");

        //移动的位置是从0 逐渐增加的
        //所以可以在外面套一层循环
        for (int j = 0; j < a.length-1; j++) {
            for (int i = j+1; i < a.length; i++) {
                if(a[i]<a[j]){
                    int temp = a[j];
                    a[j] = a[i];
                    a[i] = temp;
                }
            }
        }

        //把内容打印出来
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i] + " ");
        }
        System.out.println(" ");
    }
}

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        int n=input.nextInt();   //输入数组长度

        int a [] = new int[n];
        for (int i=0;i<n;i++){        //为数组赋值
            int x=input.nextInt();
            a[i]=x;
        }

        for (int j = 0; j < a.length; j++) {
            for (int i = 0; i < a.length-j-1; i++) {
                if(a[i+1]<a[i]){
                    int temp = a[i];
                    a[i] = a[i+1];
                    a[i+1] = temp;
                }
            }
        }



        //把内容打印出来
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i] + " ");
        }
        System.out.println(" ");
    }
}

public class Main {
    public static void main(String[] args) {

        int[] arr=new int[5];

        for (int i=0;i<5;i++){

            arr[i]=(int)(Math.random()*100);
        }

        for (int i=0;i<arr.length;i++){
            System.out.print(arr[i]+" ");
        }
        System.out.println();
        System.out.println("-----选择排序----");
        //选择正排序  即是从小到大排序
        for (int j=0;j<arr.length-1;j++){
            for (int i=j+1;i<arr.length;i++){
                if (arr[i]<arr[j]){
                    int temp=arr[j];
                    arr[j]=arr[i];
                    arr[i]=temp;
                }
            }
        }

        for (int i=0;i<arr.length;i++){
            System.out.print(arr[i]+" ");
        }
       System.out.println();

        System.out.println("-----冒泡排序----");

        for(int j=0;j<arr.length;j++){
           for ( int i=0;i<arr.length-j-1;i++){
               if(arr[i+1]<arr[i]){
                   int temp=arr[i];
                   arr[i]=arr[i+1];
                   arr[i+1]=temp;
               }
           }
        }
        for(int i=0;i<arr.length;i++){
            System.out.print(arr[i]+" ");
        }

    }
}