 | Chapter 12 |  |
Queue
A Queue is an ordered data structure. Elements are appended to the end of a queue (add) and are removed (remove) from the beginning of a queue. Therefore, this data structure is also known as FIFO (first-in-first-out).
// cityToVisit of the Queue interface has functionality of the LinkedList
Queue<String> cityToVisit = new LinkedList<>();
cityToVisit.add("Tartu"); // adds the element to the end of the list
cityToVisit.add("Paide");
cityToVisit.add("Tallinn");
while (!cityToVisit.isEmpty()) {
System.out.println(cityToVisit.remove()); // removes the first element of the list
}
Queues are used in graphs and in the program flow control (user inputs are stored in a queue and later they are executed in FIFO order).
| Chapter 12 | |