📅 Date: Jan 13, 2026
🔥 Topic: 2D Arrays (Matrices)

⬛ Rows and Columns

Sometimes data isn't a straight line; it's a grid (like a Chessboard or an Excel sheet). For this, we use 2D Arrays.

Syntax: int arr[rows][columns];

Visualizing arr[2][3]:
[ 0, 0 ] [ 0, 1 ] [ 0, 2 ]
[ 1, 0 ] [ 1, 1 ] [ 1, 2 ]

💻 Day 13 Code: Hardcoded Matrix

#include <iostream>
using namespace std;

int main() {
    // Declaration: 3 Rows, 3 Cols
    int grid[3][3] = {
        {1, 2, 3},
        {4, 5, 6},
        {7, 8, 9}
    };

    // Accessing specific element (Row 1, Col 2)
    // Remember index starts at 0!
    cout << "Element at [1][2] is: " << grid[1][2] << endl; 
    // Output should be 6

    return 0;
}

💭 Thoughts

It's basically an "Array of Arrays". To handle this, I will need Nested Loops (a loop inside a loop) tomorrow.