Computer scienceProgramming languagesJavaWorking with dataCollectionsCollections framework

The List interface

Theory

Backward indexes

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Implement a method that returns an element by the specified index from a list. The method must return an element by its regular or backward index.

In the regular order, elements have indexes 0, 1, 2, ..., n – 1. In the backward order, the same elements have indexes -n, -n + 1, ..., -2, -1; where n is the size of a list.

If the specified index is out of bounds, the method must throw the standard IndexOutOfBoundsException.

Example. The input list consists of four elements: [100 202 300 401]. If the specified index is 0, the method should return 100; if the specified index is -1 the method should return 401; if the specified index is -2, the method should return 300.

Sample Input 1: 

100 202 300 401
0

Sample Output 1: 

100

Sample Input 2: 

100 202 300 401
-1

Sample Output 2: 

401

Sample Input 3: 

100 202 300 401
-2

Sample Output 3: 

300
Write a program in Java 17
import java.util.*;
import java.util.stream.Collectors;

public class Main {

public static <T> T getElementByIndex(List<T> lst, int index) {
// write your code here
}

/* Do not change code below */
public static void main(String[] args) {

final Scanner scanner = new Scanner(System.in);

final List<String> values = Arrays
.stream(scanner.nextLine().split("\\s+"))
.collect(Collectors.toList());

final int index = Integer.parseInt(scanner.nextLine());

try {
String element = getElementByIndex(values, index);
System.out.println(element);
} catch (IndexOutOfBoundsException e) {
System.out.println("Exception");
}
}
}
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