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2 changes: 1 addition & 1 deletion src/navs/documentation.js
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,6 @@ export const documentationNav = {
pages['break-statement'],
pages['continue-statement'],
],
'Java Arrays': [pages['arrays']],
'Java Arrays': [pages['arrays'], pages['multidimensional-arrays']],
'Java OOPS': [pages['static-keyword']],
}
208 changes: 208 additions & 0 deletions src/pages/docs/multidimensional-arrays.mdx
Original file line number Diff line number Diff line change
@@ -0,0 +1,208 @@
---
title: Java Multidimensional Arrays
description: In this tutorial, we will learn how to use the Java continue statement to skip the current iteration of a loop.
---

## Java Multidimensional Arrays
Before we learn about the multidimensional array, make sure you know about Java array.

A multidimensional array is an array of arrays. Each element of a multidimensional array is an array itself. For example,

```java
int[][] a = new int[3][4];
```
Here, we have created a multidimensional array named a. It is a 2-dimensional array, that can hold a maximum of 12 elements,

![2-dimensional array in Java](https://via.placeholder.com/600x400?text=2-dimensional+array+in+Java)
2-dimensional Array

Remember, Java uses zero-based indexing, that is, indexing of arrays in Java starts with 0 and not 1.

Let's take another example of the multidimensional array. This time we will be creating a 3-dimensional array. For example,

```java
String[][][] data = new String[3][4][2];
```
Here, data is a 3d array that can hold a maximum of 24 (3*4*2) elements of type [String](/docs/string).

### How to initialize a 2d array in Java?
Here is how we can initialize a 2-dimensional array in Java.

```java
int[][] a = {
{1, 2, 3},
{4, 5, 6, 9},
{7},
};
```
As we can see, each element of the multidimensional array is an array itself. And also, unlike C/C++, each row of the multidimensional array in Java can be of different lengths.


![2d array example in Java with variable length](https://via.placeholder.com/600x400?text=2d+array+example+in+Java+with+variable+length)
Initialization of 2-dimensional Array

### Example: 2-dimensional Array
```java
class MultidimensionalArray {
public static void main(String[] args) {

// create a 2d array
int[][] a = {
{1, 2, 3},
{4, 5, 6, 9},
{7},
};

// calculate the length of each row
System.out.println("Length of row 1: " + a[0].length);
System.out.println("Length of row 2: " + a[1].length);
System.out.println("Length of row 3: " + a[2].length);
}
}
```
#### Output:

```plaintext
Length of row 1: 3
Length of row 2: 4
Length of row 3: 1
```
In the above example, we are creating a multidimensional array named a. Since each component of a multidimensional array is also an array (`a[0]`,`a[1]` and `a[2]` are also arrays).

Here, we are using the `length` attribute to calculate the length of each row.

### Example: Print all elements of 2d array Using Loop

```java
class MultidimensionalArray {
public static void main(String[] args) {

int[][] a = {
{1, -2, 3},
{-4, -5, 6, 9},
{7},
};

for (int i = 0; i < a.length; ++i) {
for(int j = 0; j < a[i].length; ++j) {
System.out.println(a[i][j]);
}
}
}
}
```
#### Output:

```plaintext
1
-2
3
-4
-5
6
9
7
```
We can also use the [for...each loop](/docs/enhanced-for-loop) to access elements of the multidimensional array. For example,

```java
class MultidimensionalArray {
public static void main(String[] args) {

// create a 2d array
int[][] a = {
{1, -2, 3},
{-4, -5, 6, 9},
{7},
};

// first for...each loop access the individual array
// inside the 2d array
for (int[] innerArray: a) {
// second for...each loop access each element inside the row
for(int data: innerArray) {
System.out.println(data);
}
}
}
}
```
Output:

```plaintext
1
-2
3
-4
-5
6
9
7
```
In the above example, we are have created a 2d array named `a`. We then used `for` loop and `for...each` loop to access each element of the array.

### How to initialize a 3d array in Java?
Let's see how we can use a 3d array in Java. We can initialize a 3d array similar to the 2d array. For example,

```java
// test is a 3d array
int[][][] test = {
{
{1, -2, 3},
{2, 3, 4}
},
{
{-4, -5, 6, 9},
{1},
{2, 3}
}
};
```
Basically, a 3d array is an array of 2d arrays. The rows of a 3d array can also vary in length just like in a 2d array.

### Example: 3-dimensional Array
```java
class ThreeArray {
public static void main(String[] args) {

// create a 3d array
int[][][] test = {
{
{1, -2, 3},
{2, 3, 4}
},
{
{-4, -5, 6, 9},
{1},
{2, 3}
}
};

// for..each loop to iterate through elements of 3d array
for (int[][] array2D: test) {
for (int[] array1D: array2D) {
for(int item: array1D) {
System.out.println(item);
}
}
}
}
}
```
#### Output:

```plaintext
1
-2
3
2
3
4
-4
-5
6
9
1
2
3
```
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