How arrays work in Java (illustration)


An array is an expression that prepares a box for storing data side by side and puts it in and out. There are two types of arrays: one-dimensional arrays and multidimensional arrays. I will explain the mechanism of the array using an example.

One-dimensional array

Let's substitute 1,2,3,4,5 for each element of the array and display it.


class Array {
	public static void main(String[] args) {

		int[] a = new int[5];

		for (int i = 0; i < a.length; i++){
			a[i] = i + 1;

		for (int i = 0; i < a.length; i++){
			System.out.println("a[" + i + "] = " + a[i]);
【Execution result】


Multidimensional array

Let's substitute 1,2,3,4,1,2,3,4 for each element of the array and display it.


class A2 {
	public static void main(String[] args) {

			int[][] x = new int[2][4];

			for (int i = 0; i < 2; i++) {
				for (int j = 0; j < 4; j++) {
					x[i][j] = j + 1;
					System.out.println("x[" + i + "][" + j + "] = " + x[i][j]);
【Execution result】
x[0][0] = 1
x[0][1] = 2
x[0][2] = 3
x[0][3] = 4
x[1][0] = 1
x[1][1] = 2
x[1][2] = 3
x[1][3] = 4


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