1. 什么是Queue和Deque?
import java.util.LinkedList;
import java.util.Queue;
public class QueueExample {
public static void main(String[] args) {
Queue<String> queue = new LinkedList<>();
// 添加元素到队列
queue.offer("A");
queue.offer("B");
queue.offer("C");
// 获取并删除队头元素
String head = queue.poll();
System.out.println("Head of the queue: " + head);
// 获取但不删除队头元素
String peek = queue.peek();
System.out.println("Peek of the queue: " + peek);
}
}
import java.util.ArrayDeque;
import java.util.Deque;
public class DequeExample {
public static void main(String[] args) {
Deque<String> deque = new ArrayDeque<>();
// 从队头添加元素
deque.addFirst("A");
deque.addFirst("B");
// 从队尾添加元素
deque.addLast("C");
// 从队头获取并删除元素
String first = deque.pollFirst();
System.out.println("First element: " + first);
// 从队尾获取并删除元素
String last = deque.pollLast();
System.out.println("Last element: " + last);
}
}