构建基础的字符串队列实现方法

队列就是先进先出&＃xff0c;没有什么难点。注意 Java 没有指针&＃xff0c;相当于用嵌套的类模拟指针建成链表。

public class LinkedQueueOfStrings
{private class Node{String item;Node next;}private Node first, last;public void enqueue(String item){Node oldlast &＃61; last;last &＃61; new Node();last.item &＃61; item;last.next &＃61; null;if (isEmpty()) first &＃61; last;else oldlast.next &＃61; last;}String dequeue(){String item &＃61; first.item;first &＃61; first.next;if (isEmpty()) last &＃61; null;return item;}boolean isEmpty(){ return first &＃61;&＃61; null; }int size(){int num &＃61; 0;for(Node i &＃61; first; i !&＃61; last; i &＃61; first.next)num&＃43;&＃43;;return num &＃43; 1;}public static void main(String[] argv){LinkedQueueOfStrings queue &＃61; new LinkedQueueOfStrings();queue.enqueue("huangyi");queue.enqueue("jiahai");System.out.println(queue.dequeue());}
}

参考

https://class.coursera.org/algs4partI-010/lecture/20