Question

1. Write a program to ask user to enter an integer that represents the number of elements, then generate an ArrayList containing elements which are all random integers in range [75, 144] , and finally display index and value of each element.

REQUIREMENTS

• The user input is always correct (input verification is not required).
• Your code must use ArrayList.
• Your program must use only printf(…) statements to adjust the alignment of your output.
• Your code must display the index in descending order.
• Your output must be displayed with the same alignment as the example (the text in bold indicates the user input).

Example of the program output:

Example 1:

Enter the number of elements: 5

Index   Element

4       129   

3       138   

2       134   

1       98    

0       84

Example 2:

Enter the number of elements: 12

Index   Element

11      109   

10      80    

9       122   

8       84    

7       142   

6       114   

5       114   

4       111   

3       82    

2       91    

1       132   

0       113

Answer 1

import java.util.ArrayList;
import java.util.Random;
import java.util.Scanner;

public class RandomList {
   public static void main(String[] args) {
       Scanner sc = new Scanner(System.in);
       System.out.print("Enter the number of elements: ");
       int n = sc.nextInt();
       Random r = new Random();
       ArrayList<Integer>list = new ArrayList<>();
       for(int i=0;i<n;i++)
           list.add(r.nextInt(200));
       System.out.println("Index\tElement");
       for(int i=list.size()-1;i>=0;i--)
           System.out.println(i+"\t"+list.get(i));
   }
}