Single and Multi-Dimensional Arrays in C#

Arrays in C# are a fundamental data structure used to store a collection of elements of the same data type. They provide a convenient way to organize and manipulate data.

There are two main types of arrays in C#:

1. Single-Dimensional Arrays 📈 A single-dimensional array stores elements in a linear sequence.

int[] numbers = new int[5]; // Declares an array of 5 integers
// Initializing the elements individually. index starts from "0"
numbers[0] = 10;
numbers[1] = 20;
numbers[2] = 30;
numbers[3] = 40;
numbers[4] = 50;

string[] fruits = { "Apple", "Banana", "Orange" }; // Initializes an array with values

// Accessing the second element of the 'numbers' array
int secondNumber = numbers[1];

// Accessing the last element of the 'fruits' array
string lastFruit = fruits[fruits.Length - 1];

//Iterating Through Arrays using FOR loop
for (int i = 0; i < numbers.Length; i++)
{
    Console.WriteLine(numbers[i]);
}

//Iterating Through Arrays using FOREACH loop
foreach (var fruit in fruits)
{
    Console.WriteLine(fruit);
}

Simple Example:

int[] scores = { 90, 85, 78, 92, 88 }; // Declare and initialize an array of scores

// Calculate the average score
int sum = 0; // Initialize a variable to store the sum of scores
foreach (int score in scores) // Iterate through each score in the array
{
    sum += score; // Add the current score to the sum
}
double average = (double)sum / scores.Length; // Calculate the average by dividing the sum
            // by the number of scores, casting the sum to double to ensure floating-point division

Console.WriteLine("Average score: " + average); // Print the calculated average to the console

2. Multidimensional Arrays 🏢 Multidimensional arrays store elements in a tabular format, similar to a matrix.

int[,] matrix = new int[2, 3]; // Declares a 2x3 matrix
// Initializing the matrix
matrix[0, 0] = 1;
matrix[0, 1] = 2;
matrix[0, 2] = 3;
matrix[1, 0] = 4;
matrix[1, 1] = 5;
matrix[1, 2] = 6;
//Similar to matrix: int[number of rows, number of columns], total elements = row x column.

int[,] matrix2 = { { 1, 2, 3 }, { 4, 5, 6 } }; // Initializes a 2x3 matrix
Console.WriteLine(matrix[1, 2]); // Accesses the element at row 1, column 2

//Iterating Through Multidimensional Arrays:
for (int i = 0; i < matrix.GetLength(0); i++)
{
    for (int j = 0; j < matrix.GetLength(1); j++)
    {
        Console.Write(matrix[i, j] + " ");
    }
    Console.WriteLine();
}

Simple Example:

int[,] multiplicationTable = new int[10, 10];

// Populate the multiplication table
for (int i = 0; i < 10; i++)
{
    for (int j = 0; j < 10; j++)
    {
        multiplicationTable[i, j] = (i + 1) * (j + 1);
    }
}

// Print the multiplication table
for (int i = 0; i < 10; i++)
{
    for (int j = 0; j < 10; j++)
    {
        Console.Write(multiplicationTable[i, j] + "\t");
    }
    Console.WriteLine();
}

Key Points to Remember:

• Array indices start from 0.

• Array sizes must be specified at declaration or initialization.

• Array elements are stored in contiguous memory locations.

• Arrays are reference types, so assigning one array to another creates a reference to the same memory location.

• Multidimensional arrays can have any number of dimensions.

• Remember that array indices are zero-based, and accessing an index that is out of bounds will result in an IndexOutOfRangeException

By understanding and effectively using arrays, you can create efficient and structured data representations in your C# programs.