How To Loop Over Ii Dimensional Array Inwards Java?

You tin loop over a two-dimensional array inwards Java yesteryear using two for loops, as good known as nested loop. Similarly to loop an n-dimensional array yous postulate n loops nested into each other. Though it's non mutual to run across an array of to a greater extent than than three dimension as well as 2D arrays is what yous volition run across most of the places. It's i of the most useful information construction inwards the programming world. You tin purpose a two-dimensional array to brand finite field machine (FSM) solve field based problems, yous tin purpose a 2D array to create board games similar Chess, Sudoku as well as Tic-Tac-To as well as yous tin fifty-fifty purpose a two-dimensional array to create 2D arcade games e.g. Tetris, Super Mario Bros as well as hence on. Whatever yous run across on your shroud is nix but a 2D array which is populated using tiles.

In gild to brand purpose of the 2D array, yous must know how to populate as well as iterate over it as well as that's what yous volition larn inwards this article. You tin cry upwardly nearly ii dimensional array as a matrix which has rows as well as columns, this aid to visualize contents of an array. In gild to loop over a 2D array, nosotros kickoff become through each row as well as and hence i time again nosotros become through each column inwards every row. That's why nosotros postulate ii loops, nested inwards each other.

Anytime, if yous desire to come upwardly out of nested loop, yous tin purpose the interruption statement. If yous are an absolute beginner as well as simply started amongst 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 inwards Java

Here is a Java programme to iterate over a ii dimensional array inwards Java using traditional for loop. Though it's non necessary to purpose for loop, yous tin fifty-fifty purpose patch loop or advanced for loop inwards Java, it makes feel to start amongst this simplest of programming construct.

In this example, nosotros bring kickoff created a 2 dimensional array of size 4x4, which way four rows as well as four columns. Then nosotros bring looped over it ii times, kickoff fourth dimension to populate the array amongst integer values as well as the minute fourth dimension to become through each index as well as impress their values.

It's non necessary to start looping from kickoff chemical ingredient e.g. [0, 0] which is kickoff row as well as kickoff column but if yous desire to touching on every chemical ingredient this is the correct house to start.

Here is the code to loop over 2D array inwards 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 run across that outer loop is going through each row as well as the inner loop is going through each column, this way nosotros become over all elements. In the kickoff iteration, all elements of the kickoff row are processed, simply similar iterating over i dimensional array.

Here is the consummate programme :

Looping over 2D array inwards Java

/**  * Java Program to demonstrate how to loop over two-dimensional array.  * We kickoff loop to populate the array as well as afterward 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 as well as 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 bring multi-dimensional arrays, instead, yous bring arrays of arrays (of arrays ...). So, if yous desire to loop through the kickoff 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 as well as tin hold upwardly used to stand upwardly for board games e.g. Chess, Ludo, Sudoku, Tetris as well as as good every bit useful to describe terrains inwards tile based games. In fact, it is i of the most useful information construction inwards game programming. Another natural purpose of a multi-dimensional array is inwards matrix maths e.g. matrix multiplication, adding ii matrices, transposing matrices etc.

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

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

22 Array concept Interview Questions inwards Java (see here)

How to impress array values inwards Java? (example)

How to compare ii arrays inwards Java? (example)

Data Structures as well as Algorithm Analysis inwards Java (see here)

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