Unit 3 Lesson 1 - One Dimensional (1D) Arrays

Lesson summary and assignments

data structure

a structure for organizing, processing, retrieving, and storing data

element

a single value or object in a data structure

one-dimensional (1D) array

a data structure that holds multiple values of the same data type

    //Declare and instantiate array
    String[] colors = new String[5];

    //Initialize the array elements
    colors[0] = "Orange";
    colors[1] = "Yellow";
    colors[2] = "Blue";
    colors[3] = "Red";
    colors[4] = "Green";

    //Print the number of elements in the array
    System.out.println(colors.length); //Prints 5
                

• All elements are of the same type (in this case: String)
• Index starts at zero
• Last index is length of the array minus 1

Alternatively, you can initialize the array with an initializer list. The number of entries in the initializer list determines the size of the array. In this case, temperatures.length returns 6

    //Declare a temperatures array and initialize it with 6 values
    double[] temperatures = {78.3, 87.1, 79.8, 92.3, 88.0, 81.6}
                

Answers

Vocabulary

data structure

a structure for organizing, processing, retrieving, and storing data

element

a single value or object in a data structure

one-dimensional (1D) array

a data structure that holds multiple values of the same data type