Java Arrays

An array holds several values of the same type. Its size is fixed when you create it, and positions (indexes) start at 0.

ExampleJava

import java.util.Arrays;

public class Main {
  public static void main(String[] args) {
    String[] cars = {"Volvo", "BMW", "Ford"};
    System.out.println(cars[0]);        // Volvo
    cars[1] = "Opel";
    System.out.println(cars.length);    // 3
    System.out.println(Arrays.toString(cars));

    int[] nums = new int[3];            // {0, 0, 0}
    nums[2] = 7;
    System.out.println(Arrays.toString(nums));

    int[] scores = {5, 2, 9, 1};
    Arrays.sort(scores);
    System.out.println(Arrays.toString(scores));

    int[][] grid = {{1, 2}, {3, 4}};    // 2D array
    System.out.println(grid[1][0]);     // 3
  }
}

Output

Volvo
3
[Volvo, Opel, Ford]
[0, 0, 7]
[1, 2, 5, 9]
3

Quick check

What is the index of the first element of an array?

01-1

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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