Autoboxing and foreach
In this exercise, you will explore autoboxing and looping through a List - specifically a LinkedList of prices. You will add some double values to the LinkedList, allowing autoboxing to convert them to Double, and use the “foreach” loop to calculate the average price of the items in the LinkedList that has been imported for you.
Este exercício faz parte do curso
Data Types and Exceptions in Java
Instruções do exercício
- Construct a new
LinkedListofDoubles and set thepricesvariable to it. - Add a new price (a
double)9.65to the end of thepriceslist. Autoboxing will automatically convert thedoubleto aDoublebefore adding it. - Add a new price (a
double)1.35to the beginning of thepriceslist. Autoboxing will automatically convert thedoubleto aDoublebefore adding it. - Use a "foreach" loop to iterate through and sum all prices.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
public class Averaging {
public static void main(String[] args) {
// Create a LinkList of Doubles using parameterized constructor
____<____> prices = ____ ____<____>();
prices.add(5.60);
// Add 9.65 to the end of the list
prices.____(____);
prices.add(3.40);
// Add 1.35 to the start of the list
prices.____(____);
System.out.println(prices);
Double total = 0.0;
// Use for each to loop through all the prices
____ (____ price : ____) {
total += price;
}
System.out.println("Average price: " + total/prices.size());
}
}