Array Methods

Part of the Fundamentals section of Coddy's Java journey. Lesson 61 of 73.

The Arrays class (from java.util) provides many helper methods for working with arrays. To call one, write:

Arrays.methodName(arrayName, otherParameters)

Here is a list of the basic methods:

fill(array, value) - fills the array with a specific value

toString() - converts the array to a string

sort(array) - sorts the array in ascending order

equals(array1, array2) - compares two arrays to determine if they are equal

Here is an example of how to use the fill method with toString:

int[] numbers = new int[5];
Arrays.fill(numbers, 10);
System.out.println(Arrays.toString(numbers));

This will output [10, 10, 10, 10, 10].

Example of the sort method:

int[] numbers = {5, 2, 9, 1, 5, 6};
Arrays.sort(numbers);
System.out.println(Arrays.toString(numbers));

This will output [1, 2, 5, 5, 6, 9].

Challenge

Easy

Create a method named merge that receives two arrays as arguments. The method merges the two arrays into one sorted array and returns it.

Important: The final merged array must be sorted in ascending order.

For example the following arguments: merge(new String[] {"1", "4", "2"}, new String[] {"2", "5", "9"}) will return ["1", "2", "2", "4", "5", "9"] (notice the result is sorted)

Use System.arraycopy() to copy elements from one array to another. The syntax is:

System.arraycopy(sourceArray, sourceStartPosition, destinationArray, destinationStartPosition, length)

System.arraycopy() only copies into an array that already exists; it never grows the destination. Create the merged array with arr1.length + arr2.length slots first, copy arr1 to position 0, then copy arr2 starting at position arr1.length.

For example:

// Source array
String[] sourceArray = {"1", "2", "3", "4", "5"};
        
// Destination array
String[] destinationArray = new String[5];
        
// Copy elements from sourceArray to destinationArray
System.arraycopy(sourceArray, 0, destinationArray, 0, 5);

Destination array after copy: 1 2 3 4 5

Try it yourself

import java.util.Arrays;
import java.util.Scanner;


public class Main {
    public static String[] merge(String[] arr1, String[] arr2) {
        // Write code here
        return null;
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String textArr1 = scanner.nextLine();
        String textArr2 = scanner.nextLine();
        String[] arr1 = textArr1.split(",");
        String[] arr2 = textArr2.split(",");

        String[] mergedArray = merge(arr1, arr2);
        System.out.println(Arrays.toString(mergedArray));
    }
}