Array in C++

An array is a fixed-size collection of elements of the same data type that are stored in contiguous memory locations. It provides a convenient way to store and access multiple values using a single variable name. The elements in an array can be accessed using their index, which starts from 0 and goes up to the size of the array minus 1.

Syntax

The syntax for declaring an array in C++ is as follows:

type array_name[array_size];

Here's a breakdown of each component:

  • type represents the data type of the elements in the array.
  • array_name is the name of the array variable.
  • array_size specifies the number of elements that the array can hold.

For example, to declare an integer array of size 5 named numbers, you would write:

int numbers[5];

Accessing Array Elements

Array elements can be accessed using their index, which starts at 0 and goes up to array_size - 1. To access an element at a specific index, use the following syntax: 

array_name[index];

For example, to access the third element of the numbers array, you would write:

int thirdElement = numbers[2];

In this case, numbers[2] retrieves the value at index 2 (the third element) and assigns it to the thirdElement variable.

Example

Let's consider a simple example to illustrate the usage of arrays:

#include<iostream>
using namespace std;
int main() {
    int numbers[5] = {10, 20, 30, 40, 50};
    for (int i = 0; i < 5; i++) {
        cout << numbers[i] << " ";
    }
    return 0;
}

In this example, we have an integer array named numbers initialized with values. The program uses a for loop to iterate over each element of the array and displays them on the console.

The output of this program would be:

10 20 30 40 50

Types of Usage

Arrays can be used in various ways to store and manipulate data efficiently. Here are some common types of usage:

Storing Multiple Values

Arrays allow you to store multiple values of the same data type in a single variable. This is useful when you need to work with collections of related data, such as a list of grades, a set of coordinates, or a sequence of characters.

char name[10] = "John Doe";

In this example, the name array stores a sequence of characters representing a person's name.

Iterating Over Array Elements

You can use loops, such as for or while, to iterate over array elements and perform operations on them. This is helpful when you need to process each element in the array or perform calculations based on the values stored in the array.

int numbers[5] = {10, 20, 30, 40, 50};
for (int i = 0; i < 5; i++) {
    // Perform operations on numbers[i]
}

In this case, the for loop iterates over each element of the numbers array, allowing you to perform operations on each element.

Multidimensional Arrays

C++ supports multidimensional arrays, which are arrays with multiple dimensions or indices. This is useful for representing grids, matrices, or tables of data.

int matrix[3][3] = {
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

In this example, the matrix array represents a 3x3 matrix with integer values.

Conclusion

Arrays are a powerful feature in C++ that provide a convenient way to store and manipulate multiple elements of the same data type. By understanding the syntax and different types of usage, you can effectively work with arrays in your programs.