/** * File: deque.kt * Created Time: 2024-01-25 * Author: curtishd (1023632660@qq.com) */ package chapter_stack_and_queue import java.util.* /* Driver Code */ fun main() { /* 初始化双向队列 */ val deque = LinkedList() deque.offerLast(3) deque.offerLast(2) deque.offerLast(5) println("双向队列 deque = $deque") /* 访问元素 */ val peekFirst = deque.peekFirst() println("队首元素 peekFirst = $peekFirst") val peekLast = deque.peekLast() println("队尾元素 peekLast = $peekLast") /* 元素入队 */ deque.offerLast(4) println("元素 4 队尾入队后 deque = $deque") deque.offerFirst(1) println("元素 1 队首入队后 deque = $deque") /* 元素出队 */ val popLast = deque.pollLast() println("队尾出队元素 = $popLast,队尾出队后 deque = $deque") val popFirst = deque.pollFirst() println("队首出队元素 = $popFirst,队首出队后 deque = $deque") /* 获取双向队列的长度 */ val size = deque.size println("双向队列长度 size = $size") /* 判断双向队列是否为空 */ val isEmpty = deque.isEmpty() println("双向队列是否为空 = $isEmpty") }