Arrays in C are a powerful way to store multiple values of the same type using a single variable name. You can think of them like boxes lined up in memory — each box holds one item, and you access it by its index.

? Basics of Arrays

? Declaration

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

Or let the compiler count them:

c
int numbers[] = {10, 20, 30};

? Accessing Elements

Indexes start from 0:

c
printf("%d", numbers[0]); // prints 10numbers[1] = 25;           // changes second element to 25

? Looping Through an Array

c
#include <stdio.h>int main() {    int scores[] = {85, 90, 78, 92, 88};    int length = sizeof(scores) / sizeof(scores[0]);    for (int i = 0; i < length; i++) {        printf("Score %d: %d\n", i + 1, scores[i]);    }    return 0;}

? Types of Arrays

1. One-Dimensional Array

c
char vowels[] = {'a', 'e', 'i', 'o', 'u'};

2. Multi-Dimensional Array (2D)

c
int matrix[2][3] = {    {1, 2, 3},    {4, 5, 6}};

Access like: matrix[0][2] ? 3

?? Array Boundaries

C does not check array bounds! Be careful not to go out of range:

c
int arr[3] = {1, 2, 3};arr[5] = 10; // ? undefined behavior!

? Bonus: String as Char Array

c
char name[] = "Alice";printf("%s", name); // prints Alice

It's actually a character array: ['A', 'l', 'i', 'c', 'e', '\0']

Want help with:

• 2D array operations?

• Sorting arrays?

• Passing arrays to functions?