Multidimensional Arrays

Introduction

A multidimensional array stores data in two or more dimensions — commonly 2D arrays for matrices and grids.

Understanding the topic

2D declaration type name[rows][cols];

Row-major storage Elements stored row by row in memory.

Nested loops Access with mat[i][j] in nested for loops.

• 2D declaration — type name[rows][cols];.
• Row-major storage — Elements stored row by row in memory.
• Nested loops — Access with mat[i][j] in nested for loops.

Step-by-step explanation

1. 2D declaration — type name[rows][cols];.
2. Row-major storage — Elements stored row by row in memory.
3. Nested loops — Access with mat[i][j] in nested for loops.

Syntax reference

Syntax reference:

type arr[ROWS][COLS];

Informative example

Example program:

#include <stdio.h>

int main(void) {
    int mat[2][3] = {{1, 2, 3}, {4, 5, 6}};
    printf("%d\n", mat[1][2]);
    return 0;
}

6

Execution workflow

Real-world use

Related topics:

• Arrays in C
• Pointers and 2D arrays

Best practices

• Enable warnings: gcc -Wall -Wextra -std=c11 source.c -o app
• Give every variable a defined value before it is read.
• Stay inside array bounds — C will not stop you from over-running a buffer.

Common mistakes

• Reading uninitialized storage — behavior is undefined.
• Dismissing compiler warnings instead of fixing root causes.
• Ignoring NULL returns from malloc, fopen, and similar APIs.

Hands-on exercise

Practice problems:

• Add two matrices
• Print matrix in tabular form

Summary

Multidimensional Arrays in C — Tables and matrices stored in row-major order.