What is an array in C programming?

 In C programming, an array is a collection of elements of the same data type, stored in contiguous memory locations. Arrays allow you to store multiple values in a single variable, making it easier to manage and manipulate groups of related data. Each element in an array can be accessed using an index, which is an integer value that represents the position of the element within the array.

Key Characteristics of Arrays in C

1. Fixed Size: The size of an array must be defined at the time of declaration and cannot be changed during runtime.
2. Homogeneous Elements: All elements in an array must be of the same data type (e.g., all integers, all floats).
3. Zero-Based Indexing: Array indexing in C starts from 0. The first element is accessed with index 0, the second with index 1, and so on.

Declaring and Initializing Arrays

To declare an array in C, you specify the data type, followed by the array name and the size in square brackets. Here are some examples:

1. Declaration of an Array

int numbers[5];  // Declares an array of 5 integers

2. Initialization of an Array

You can initialize an array at the time of declaration:

int numbers[5] = {1, 2, 3, 4, 5};  // Initializes the array with values

If you do not specify the size, the compiler will determine it based on the number of initializers:

int numbers[] = {1, 2, 3, 4, 5};  // Size is automatically set to 5

Accessing Array Elements

You can access and modify elements in an array using their index:

#include <stdio.h>

int main() {

    int numbers[5] = {10, 20, 30, 40, 50};

    // Accessing elements

    printf("First element: %d\n", numbers[0]);  // Output: 10

    printf("Second element: %d\n", numbers[1]); // Output: 20

    // Modifying an element

    numbers[2] = 100;  // Change the third element to 100

    printf("Modified third element: %d\n", numbers[2]); // Output: 100

    return 0;

}

Example: Using Arrays in C

Here’s a complete example that demonstrates how to declare, initialize, and manipulate an array in C:

#include <stdio.h>

int main() {

    // Declare and initialize an array of integers

    int scores[5] = {85, 90, 78, 92, 88};

    int sum = 0;

    // Calculate the sum of the scores

    for (int i = 0; i < 5; i++) {

        sum += scores[i];  // Add each score to sum

    }

    // Calculate the average

    float average = sum / 5.0;

    // Print the results

    printf("Sum of scores: %d\n", sum);

    printf("Average score: %.2f\n", average);

    return 0;

}

Explanation of the Example

1. Declaration and Initialization: The array scores is declared and initialized with five integer values representing scores.

2. Looping Through the Array: A for loop is used to iterate through the array elements. The loop variable i serves as the index to access each element.

3. Calculating the Sum: Each score is added to the sum variable.

4. Calculating the Average: The average is calculated by dividing the total sum by the number of elements (5).

5. Output: The program prints the sum and average of the scores.

Multidimensional Arrays

C also supports multidimensional arrays, which are arrays of arrays. The most common type is the two-dimensional array, which can be thought of as a table or matrix.

Example of a Two-Dimensional Array

#include <stdio.h>

int main() {

    // Declare and initialize a 2D array

    int matrix[2][3] = {

        {1, 2, 3},

        {4, 5, 6}

    };

    // Accessing elements in a 2D array

    printf("Element at (0, 1): %d\n", matrix[0][1]); // Output: 2

    printf("Element at (1, 2): %d\n", matrix[1][2]); // Output: 6

    return 0;

}

Arrays in C are a powerful feature that allows you to store and manipulate collections of data efficiently. Understanding