# Introduction to 2-D Arrays in C++ ## Introduction to 2-D Arrays

Multidimensional Arrays can be defined in simple words as an array of arrays. Data in multidimensional arrays are stored in tabular form (in row-major order).

The 2D array is organized as matrices which can be represented as the collection of rows and columns.

##### Syntax :

The syntax of declaring a two-dimensional array is very much similar to that of a one-dimensional array, given as follows.

datatype variable_name[rows][column];

## How do we access data in a 2D array

The elements of 2D arrays can be randomly accessed. Similar to one-dimensional arrays, we can access the individual cells in a 2D array by using the indices of the cells. There are two indices attached to a particular cell, one is its row number while the other is its column number.

we can store the value stored in any particular cell of a 2D array to some variable a by using the following syntax.

int x = a[i][j]

where i is row index and j is column index . ## Size of 2-D array

The total number of elements that can be stored in a multidimensional array can be calculated by multiplying the size of all the dimensions.
For example:
The array int a can store total (5*6) = 30 elements.

## Initializing 2D Arrays

•  DIRECT METHOD

data_type[][] variable_name = { {R1C1, R1C2, ….}, {R2C1,R2C2, ….} };

Example:

int [ ][ ] arr = { { 2 ,  4 } ,  {6, 8 } };

• USING LOOPS:

We can use loops for initializing 2d array like

`for (int i = 0; i < 2; i++)  {    for (int j = 0; j < 2; j++)      {	int a = x[i][j];      }  }`

## C++ Code to show how to initialize and print 2-D array

`#include<iostream>using namespace std; int main(){    // an array with 3 rows and 2 columns.    int x = {{1,2,3}, {4,5,6}};     // output each array element's value    for (int i = 0; i < 2; i++)    {        for (int j = 0; j < 3; j++)        {            cout << "Element at x[" << i << "][" << j << "]: ";            cout << a[i][j]<<endl;        }    }     return 0;}`
`Output :Element at x: 1Element at x: 2Element at x: 3Element at x: 4Element at x: 5Element at x: 6`