How To Loop Over Ii Dimensional Array Inwards Java?

You tin loop over a two-dimensional array inward Java past times using two for loops, likewise known as nested loop. Similarly to loop an n-dimensional array yous withdraw n loops nested into each other. Though it's non mutual to encounter an array of to a greater extent than than iii dimension too 2D arrays is what yous volition encounter most of the places. It's i of the most useful information construction inward the programming world. You tin operate a two-dimensional array to brand finite the world machine (FSM) solve the world based problems, yous tin operate a 2D array to create board games similar Chess, Sudoku too Tic-Tac-To too yous tin fifty-fifty operate a two-dimensional array to create 2D arcade games e.g. Tetris, Super Mario Bros too hence on. Whatever yous encounter on your hide is nil but a 2D array which is populated using tiles.

In lodge to brand operate of the 2D array, yous must know how to populate too iterate over it too that's what yous volition acquire inward this article. You tin shout out upward most 2 dimensional array as a matrix which has rows too columns, this aid to visualize contents of an array. In lodge to loop over a 2D array, nosotros offset acquire through each row too and then over again nosotros acquire through each column inward every row. That's why nosotros withdraw 2 loops, nested inward each other.

Anytime, if yous desire to come upward out of nested loop, yous tin operate the intermission statement. If yous are an absolute beginner too only started alongside programming, I recommend reading Head First Programming first. Once yous went through the book, most of the programming concept e.g. array, string, vector volition brand feel to you.

Java Program to Loop over 2D Array inward Java

Here is a Java plan to iterate over a 2 dimensional array inward Java using traditional for loop. Though it's non necessary to operate for loop, yous tin fifty-fifty operate spell loop or advanced for loop inward Java, it makes feel to start alongside this simplest of programming construct.

In this example, nosotros accept offset created a 2 dimensional array of size 4x4, which way four rows too four columns. Then nosotros accept looped over it 2 times, offset fourth dimension to populate the array alongside integer values too the minute fourth dimension to acquire through each index too impress their values.

It's non necessary to start looping from offset chemical cistron e.g. [0, 0] which is offset row too offset column but if yous desire to deport on every chemical cistron this is the correct house to start.

Here is the code to loop over 2D array inward Java :

 for (int row = 0; row < board.length; row++) {     for (int col = 0; col < board[row].length; col++) {        board[row][col] = row * col;     }  }

You tin encounter that outer loop is going through each row too the inner loop is going through each column, this way nosotros acquire over all elements. In the offset iteration, all elements of the offset row are processed, only similar iterating over i dimensional array.

Here is the consummate plan :

Looping over 2D array inward Java

/**  * Java Program to demonstrate how to loop over two-dimensional array.  * We offset loop to populate the array too after to impress values.   *   * @author WINDOWS 8  */ public class TwoDimensionalArrayDemo{      public static void main(String args[]) {          // let's create board of 4x4         int[][] board = new int[4][4];          // let's loop through array to populate board         for (int row = 0; row < board.length; row++) {             for (int col = 0; col < board[row].length; col++) {                 board[row][col] = row * col;             }         }          // let's loop through array to impress each row too column         for (int row = 0; row < board.length; row++) {             for (int col = 0; col < board[row].length; col++) {                 board[row][col] = row * col;                 System.out.print(board[row][col] + "\t");             }             System.out.println();         }     }  }

Output :

0   0   0   0    0   1   2   3    0   2   4   6    0   3   6   9    

BTW, Java doesn't actually accept multi-dimensional arrays, instead, yous accept arrays of arrays (of arrays ...). So, if yous desire to loop through the offset array, yous inquire for "board[0].length", if yous desire to loop through the minute array, yous inquire for "board[1].length".

As I told you, a multi-dimensional array is i of the pop information construction too tin travel used to correspond board games e.g. Chess, Ludo, Sudoku, Tetris too likewise as useful to depict terrains inward tile based games. In fact, it is i of the most useful information construction inward game programming. Another natural operate of a multi-dimensional array is inward matrix maths e.g. matrix multiplication, adding 2 matrices, transposing matrices etc.

You tin extend this technique to loop through the multi-dimensional array inward Java. You volition only withdraw as many loops as many dimension your array has. Remember, yous tin declare a two-dimensional array inward Java without specifying the length of the minute dimension.

Further Learning
Data Structures too Algorithms: Deep Dive Using Java
here)

22 Array concept Interview Questions inward Java (see here)

How to impress array values inward Java? (example)

How to compare 2 arrays inward Java? (example)

Data Structures too Algorithm Analysis inward Java (see here)