custom exception

import java.util.Arrays;
import java.util.Scanner;
public class Custom {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int[] arr = new int[5];
        for(int i=0;i<5; ){
            System.out.println("Enter marks: "+(i+1));
            arr[i]=sc.nextInt();
        
            if(arr[i]<0 ||arr[i]>20){
                try{
                    throw new InvalidMarksException(arr[i]+" ");
                }catch(InvalidMarksException e){
                    System.out.println(e);
                }
            }
            else{i++;}
            System.out.println(Arrays.toString(arr));
        
        }
    }
}
  
  ////
  
  
import java.util.*;
class InvalidMarksException extends Exception{
 InvalidMarksException(){
    super("marks are invalid");
 }   
 InvalidMarksException(String msg){
    super("marks are invalid"+msg);

 }
 public String tostring(){
    return super.getMessage();
 }
}