C++ Arrays

What is an Array in C++?

A C++ array lets you store many values of the same type in a single variable. It’s like having a row of mailboxes 📬—each with its own index number.

Instead of creating 5 separate variables, you can create one array and access each item using its index.

📦 Declaring and Initializing an Array

type arrayName[size];

For example:

int numbers[5];  // Declaration
int marks[3] = {90, 85, 88};  // Initialization with values

🧪 Example: Basic Array

#include <iostream>
using namespace std;

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

    for (int i = 0; i < 5; i++) {
        cout << "Element " << i << ": " << numbers[i] << endl;
    }

    return 0;
}
  

🔢 Array Index Starts From 0

In C++, array indexing starts from 0. So the first element is at index 0, not 1.

📘 Modify Array Elements

You can change an element using its index:

numbers[2] = 99;  // Changes the third element to 99

✅ Looping Through an Array

The for loop is perfect for arrays:

for (int i = 0; i < size; i++) {
    cout << arrayName[i];
}

💡 Summary

• Array = a collection of same-type values
• Indexing starts from 0
• You can loop through it easily

Arrays help you store more in one place—like a list of scores, names, or sensor values. 🧠💾