出现编译错误 Main.java:23: error: class, interface, or enum expected import java.util.Scanner; ^

class Student{
protected String name;
protected int age;
Student(String name,int age){
this.name=name;
this.age=age;
}
public void show(){
System.out.println("Student["+"name="+name+","+"age="+age+"]");
}
}
class Undergraduate extends Student{
private String major;
Undergraduate(String name,int age,String major){
super(name,age);
this.major=major;
}
public void show(){
System.out.println("Undergraduate"+"["+"name="+name+","+"age="+age+","+"major="+major+"]");
}
}

import java.util.Scanner;

public class Main {
public static void main(String args[]){
Scanner scan = new Scanner(System.in);
Student object1=new Student(scan.next(),scan.nextInt());//创建实例对象
Undergraduate object2=new Undergraduate(scan.next(),scan.nextInt(),scan.next());//创建实例对象
object1.show();
object2.show();
}
}

改好了

import java.util.Scanner;

public class Main {
public static void main(String args[]){
Scanner scan = new Scanner(System.in);
Student object1=new Student(scan.next(),scan.nextInt());//创建实例对象
Undergraduate object2=new Undergraduate(scan.next(),scan.nextInt(),scan.next());//创建实例对象
object1.show();
object2.show();
}
}
class Student{
protected String name;
protected int age;
Student(String name,int age){
this.name=name;
this.age=age;
}
public void show(){
System.out.println("Student["+"name="+name+","+"age="+age+"]");
}
}
class Undergraduate extends Student{
private String major;
Undergraduate(String name,int age,String major){
super(name,age);
this.major=major;
}
public void show(){
System.out.println("Undergraduate"+"["+"name="+name+","+"age="+age+","+"major="+major+"]");
}
}