双向循环链表

定义双向循环链表，解决如下的问题：


有 n 个孩子顺时针站成一圈，其编号为：1，2，3，... n


从1号孩子开始顺时针数数，每个孩子数一个数，遇到7的倍数或数字中含有7，则该孩子不出声，只拍一下手，数数的方向逆转，下一个孩子数下一个数字。


例如：1,2,3...6,拍手,则接下来，6号孩子数8，5号孩子数9 ....

请模拟该过程，如果有20个孩子，求哪个孩子要数100。

public class Node<T> {T data;Node prior;Node next;Node(T data, Node<T> prior, Node<T> next) {this.data = data;this.prior = prior;this.next = next;}Node() {this.next = null;this.prior = null;}public void insertFirst(Node<T> node) {node.next = this.next;this.next = node;this.next.next.prior = node;node.prior = this;}/*public void deleteFirst() {this.next = this.next.next;this.next.prior = this;}public void tranversDList() {Node<T> node = this.next;while (node != null) {System.out.println("The data of this node is " + node.data);node = node.next;}}*/public void showNode() {System.out.println("The data of this node is:" + this.data);}}

import java.util.Scanner;public class Test {//判断方向static boolean direction(int number,boolean direct){if (number%7==0)direct=!direct;elsewhile (number>10){int j=number/10;number%=10;if (number==7){direct=!direct;break;}number=j;}return  direct;}//主函数public static void main(String[] args) {boolean clockwise = true; Node<Integer> dhead = new Node<Integer>(1, null, null); dhead.prior = dhead;dhead.next = dhead;Scanner sc = new Scanner(System.in);int num = 0;while (num < 10) {System.out.print("游戏人数(>=10):");num = sc.nextInt();}for (int i = num; i > 1; i--) {Node<Integer> node = new Node<Integer>(i, null, null);dhead.insertFirst(node);}Node<Integer> pointer = new Node<Integer>();pointer = dhead;System.out.print("数到第几个数：");num = sc.nextInt();int i = 1;while (i <= num) {System.out.print(i+"-->");pointer.showNode();clockwise = direction(i, clockwise);if (clockwise == true)pointer = pointer.next;elsepointer = pointer.prior;i++;}}}

结果：

Conclusion游戏人数(>=10):20数到第几个数：1001-->The data of this node is:12-->The data of this node is:23-->The data of this node is:34-->The data of this node is:45-->The data of this node is:56-->The data of this node is:67-->The data of this node is:78-->The data of this node is:69-->The data of this node is:510-->The data of this node is:411-->The data of this node is:312-->The data of this node is:213-->The data of this node is:114-->The data of this node is:2015-->The data of this node is:116-->The data of this node is:217-->The data of this node is:318-->The data of this node is:219-->The data of this node is:120-->The data of this node is:2021-->The data of this node is:1922-->The data of this node is:2023-->The data of this node is:124-->The data of this node is:225-->The data of this node is:326-->The data of this node is:427-->The data of this node is:528-->The data of this node is:429-->The data of this node is:530-->The data of this node is:631-->The data of this node is:732-->The data of this node is:833-->The data of this node is:934-->The data of this node is:1035-->The data of this node is:1136-->The data of this node is:1037-->The data of this node is:938-->The data of this node is:1039-->The data of this node is:1140-->The data of this node is:1241-->The data of this node is:1342-->The data of this node is:1443-->The data of this node is:1344-->The data of this node is:1245-->The data of this node is:1146-->The data of this node is:1047-->The data of this node is:948-->The data of this node is:1049-->The data of this node is:1150-->The data of this node is:1051-->The data of this node is:952-->The data of this node is:853-->The data of this node is:754-->The data of this node is:655-->The data of this node is:556-->The data of this node is:457-->The data of this node is:558-->The data of this node is:459-->The data of this node is:360-->The data of this node is:261-->The data of this node is:162-->The data of this node is:2063-->The data of this node is:1964-->The data of this node is:2065-->The data of this node is:166-->The data of this node is:267-->The data of this node is:368-->The data of this node is:269-->The data of this node is:170-->The data of this node is:2071-->The data of this node is:172-->The data of this node is:273-->The data of this node is:374-->The data of this node is:475-->The data of this node is:576-->The data of this node is:677-->The data of this node is:778-->The data of this node is:679-->The data of this node is:580-->The data of this node is:481-->The data of this node is:382-->The data of this node is:283-->The data of this node is:184-->The data of this node is:2085-->The data of this node is:186-->The data of this node is:287-->The data of this node is:388-->The data of this node is:289-->The data of this node is:190-->The data of this node is:2091-->The data of this node is:1992-->The data of this node is:2093-->The data of this node is:194-->The data of this node is:295-->The data of this node is:396-->The data of this node is:497-->The data of this node is:598-->The data of this node is:499-->The data of this node is:5100-->The data of this node is:6