Modifying Arrays

Part of the Fundamentals section of Coddy's C# journey — lesson 57 of 69.

In addition to accessing the elements of an array, you can also modify them. To modify a specific element in an array, you can assign a new value to it using its index.

Here's an example:

string[] my_array = {"apple", "banana", "cherry"};
my_array[1] = "orange";
System.Console.WriteLine(my_array[0] + ", " + my_array[1] + ", " + my_array[2]);

Output:

apple, orange, cherry

banana was changed to an orange

Challenge

Easy

Create a method named ChangeElement that receives 3 arguments:

First argument is an array
Second argument is an index
Third argument is a new element

The method will return a modified array by changing the element at the index stored in the second argument with the value in the third argument.

For example with the following arguments: ChangeElement(new string[] {"1", "2", "3"}, 0, "9") the method will return ["9", "2", "3"]

Input format (3 lines):

Line 1: the array elements separated by commas (e.g. a,b,c)
Line 2: the index of the element to replace (e.g. 1)
Line 3: the new element value (e.g. d)

Output format: the modified array elements separated by spaces (e.g. a d c )

Cheat sheet

To modify an array element, assign a new value using its index:

string[] my_array = {"apple", "banana", "cherry"};
my_array[1] = "orange";  // Changes "banana" to "orange"

Try it yourself

using System;

public class Program {
    public static string[] ChangeElement(string[] arr, int index, string newElement) {
        // Write code here
    }

    public static void Main(string[] args) {
        string textArray = Console.ReadLine();
        int index = int.Parse(Console.ReadLine());
        string newElement = Console.ReadLine();
        string[] arr = textArray.Split(',');
        string[] modifiedArr = ChangeElement(arr, index, newElement);
        for (int i = 0; i < modifiedArr.Length; i++) {
            Console.Write(modifiedArr[i] + " ");
        }
    }
}