We will learn about arrays.

  1. concept

It is a data structure that stores multiple pieces of data of the same type in a contiguous memory space. Access each element through index

  1. one-dimensional array
type name[size];
  • declare: int arr[5];
  • Init: int arr[5] = {1,2,3,4,5};
  • Default: garbage if not initialized
  1. two-dimensional array
type name[rows][columns];
    • Declaration and initialization: int mat[2][3] = {{1,2,3}, {4,5,6}};
    • Memory: row-major order
  1. example
#include <stdio.h>

int main(void) {
    int arr[5] = {10,20,30,40,50};
    printf("One-dimensional array: ");
    for (int i = 0; i < 5; i++)
        printf("%d ", arr[i]);
    printf("\n");

    int mat[2][3] = {{1,2,3},{4,5,6}};
    printf("Two-dimensional array:\n");
    for (int i = 0; i < 2; i++) {
        for (int j = 0; j < 3; j++)
            printf("%d ", mat[i][j]);
        printf("\n");
    }
    return 0;
}

I think it would be good to try this in simple practice.