What Are Multidimensional Arrays?
A multidimensional array is essentially an array of arrays. This can be particularly useful when you need to store data in a tabular format, like a table with rows and columns.
Creating a Two-Dimensional Array
To create a two-dimensional array, you simply nest each array within its own set of curly braces:
int[][] garage = { {1, 2, 3, 4}, {5, 6, 7} };Here, garage is now an array containing two arrays as its elements.
Accessing Elements
To access the elements of the garage array, you specify two indexes: one for the array and one for the element inside that array. For example, to access the third element in the second array:
int[][] garage = { {1, 2, 3, 4}, {5, 6, 7} };System.out.println(garage[1][2]); // Outputs 7Note: Array indexes start at 0, so [0] is the first element, [1] is the second element, and so on.
Modifying Element Values
You can also change the value of an element in a multidimensional array:
int[][] garage = { {1, 2, 3, 4}, {5, 6, 7} };garage[1][2] = 9;System.out.println(garage[1][2]); // Outputs 9 instead of 7Looping Through a Multidimensional Array
Using Nested For Loops
To iterate through a two-dimensional array, you can use a for loop inside another for loop:
int[][] garage = { {1, 2, 3, 4}, {5, 6, 7} };for (int row = 0; row < garage.length; ++row) { for (int col = 0; col < garage[row].length; ++col) { System.out.println(garage[row][col]); }}Using For-Each Loops
Alternatively, you can use a for-each loop, which is often easier to read and write:
int[][] garage = { {1, 2, 3, 4}, {5, 6, 7} };for (int[] row : garage) { for (int element : row) { System.out.println(element); }}