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‎src/pages/docs/multidimensional-arrays.mdx

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---
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title: Java Multidimensional Arrays
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description: In this tutorial, we will learn how to use the Java continue statement to skip the current iteration of a loop.
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---
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## Java Multidimensional Arrays
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Before we learn about the multidimensional array, make sure you know about Java array.
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A multidimensional array is an array of arrays. Each element of a multidimensional array is an array itself. For example,
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```java
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int[][] a = new int[3][4];
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```
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Here, we have created a multidimensional array named a. It is a 2-dimensional array, that can hold a maximum of 12 elements,
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![2-dimensional array in Java](https://via.placeholder.com/600x400?text=2-dimensional+array+in+Java)
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2-dimensional Array
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Remember, Java uses zero-based indexing, that is, indexing of arrays in Java starts with 0 and not 1.
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Let's take another example of the multidimensional array. This time we will be creating a 3-dimensional array. For example,
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```java
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String[][][] data = new String[3][4][2];
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```
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Here, data is a 3d array that can hold a maximum of 24 (3*4*2) elements of type [String](/docs/string).
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### How to initialize a 2d array in Java?
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Here is how we can initialize a 2-dimensional array in Java.
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```java
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int[][] a = {
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{1, 2, 3},
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{4, 5, 6, 9},
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{7},
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};
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```
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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.
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![2d array example in Java with variable length](https://via.placeholder.com/600x400?text=2d+array+example+in+Java+with+variable+length)
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Initialization of 2-dimensional Array
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### Example: 2-dimensional Array
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```java
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class MultidimensionalArray {
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public static void main(String[] args) {
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// create a 2d array
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int[][] a = {
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{1, 2, 3},
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{4, 5, 6, 9},
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{7},
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};
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// calculate the length of each row
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System.out.println("Length of row 1: " + a[0].length);
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System.out.println("Length of row 2: " + a[1].length);
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System.out.println("Length of row 3: " + a[2].length);
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}
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}
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```
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#### Output:
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```plaintext
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Length of row 1: 3
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Length of row 2: 4
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Length of row 3: 1
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```
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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).
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Here, we are using the `length` attribute to calculate the length of each row.
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### Example: Print all elements of 2d array Using Loop
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```java
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class MultidimensionalArray {
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public static void main(String[] args) {
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int[][] a = {
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{1, -2, 3},
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{-4, -5, 6, 9},
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{7},
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};
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for (int i = 0; i < a.length; ++i) {
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for(int j = 0; j < a[i].length; ++j) {
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System.out.println(a[i][j]);
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}
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}
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}
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}
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```
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#### Output:
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```plaintext
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1
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-2
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3
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-4
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-5
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6
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9
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7
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```
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We can also use the [for...each loop](/docs/enhanced-for-loop) to access elements of the multidimensional array. For example,
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```java
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class MultidimensionalArray {
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public static void main(String[] args) {
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// create a 2d array
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int[][] a = {
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{1, -2, 3},
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{-4, -5, 6, 9},
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{7},
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};
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// first for...each loop access the individual array
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// inside the 2d array
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for (int[] innerArray: a) {
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// second for...each loop access each element inside the row
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for(int data: innerArray) {
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System.out.println(data);
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}
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}
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}
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}
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```
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Output:
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```plaintext
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1
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-2
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3
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-4
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-5
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6
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9
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7
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```
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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.
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### How to initialize a 3d array in Java?
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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,
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```java
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// test is a 3d array
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int[][][] test = {
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{
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{1, -2, 3},
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{2, 3, 4}
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},
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{
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{-4, -5, 6, 9},
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{1},
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{2, 3}
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}
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};
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```
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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.
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### Example: 3-dimensional Array
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```java
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class ThreeArray {
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public static void main(String[] args) {
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// create a 3d array
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int[][][] test = {
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{
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{1, -2, 3},
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{2, 3, 4}
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},
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{
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{-4, -5, 6, 9},
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{1},
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{2, 3}
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}
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};
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// for..each loop to iterate through elements of 3d array
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for (int[][] array2D: test) {
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for (int[] array1D: array2D) {
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for(int item: array1D) {
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System.out.println(item);
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}
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}
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}
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}
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}
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```
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#### Output:
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```plaintext
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1
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-2
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3
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2
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3
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4
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-4
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-5
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6
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9
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1
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2
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3
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```

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