Java经典算法冒泡排序

Posted 2021-01-24 fengxia

冒泡排序、

实现原理：

比较两个相邻位数的元素，将较大的元素交换到右端或左端，最大的元素就在最右端或是最左端；

 

 

从小-->大

 

 1 public class MaoPao {
 2 
 3 public static void main(String[] args) {
 4 // TODO Auto-generated method stub
 5 Scanner sc= new Scanner(System.in);
 6 int [] num = new int [5];
 7 for (int i = 0; i < num.length; i++) {
 8 System.out.println("开始输入第"+(i+1)+"个数");//输入5个整数
 9 num[i]=sc.nextInt();
10 }
11 for (int i = 0; i < num.length; i++) {
12 System.out.print(num[i]+",");//冒泡之前
13 }
14 System.out.println(" ");
15 System.out.println("开始冒泡");
16 for (int i = 0; i < num.length-1; i++) {
17 for (int j = 0; j < num.length-1-i; j++) {
18 
19 if (num[j]>num[j+1]) {
20 int temp=num[j+1];
21 num[j+1]=num[j];//交换位置
22 num[j]=temp;
23 
24 }
25 }
26 }
27 for (int i = 0; i < num.length; i++) {
28 System.out.print(num[i]+","); //冒泡之后
29 }
30 
31 }

 

 

 

 从大-->小

 

public class MaoPao {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc= new Scanner(System.in);
        int [] num = new int [5];
        for (int i = 0; i < num.length; i++) {
            System.out.println("开始输入第"+(i+1)+"个数");//输入5个整数
            num[i]=sc.nextInt();
        }
        for (int i = 0; i < num.length; i++) {
            System.out.print(num[i]+",");//冒泡之前
        }
        System.out.println(" ");
        System.out.println("开始冒泡");
        for (int i = 0; i < num.length-1; i++) {
            for (int j = 0; j < num.length-1-i; j++) {
                
                if (num[j]<num[j+1]) {
                    int temp=num[j];
                    num[j]=num[j+1];
                    num[j+1]=temp;
                            
                }
            }
        }
        for (int i = 0; i < num.length; i++) {
            System.out.print(num[i]+","); //冒泡之后
        }

    }