Josephus环类问题，java实现

package Com;import java.util.Scanner;/* * 约瑟夫环问题，有n个人组成的圈，数到3的那个人出列，下个人继续从一开始 */public class Josephus {        public static void main(String[] args) {        Scanner s = new Scanner(System.in);        int n = Integer.parseInt(s.nextLine());        Node first = new Josephus().startRun(n );        int count = 1;        while(first.next != first) {            first = first.next;            count++;            if(count == 3) {                first.PRevious.next = first.next;                first.next.previous = first.previous;                first = first.next;                count = 1;            }        }        System.out.println("最后剩下来的数字为："+first.n);    }        public Node startRun(int n) {        Node first = new Node();        first.previous = null;        first.n = n ;   //这里给链表赋值，倒叙        Node current = first;        Node last = first;        while((--n)>0) {            current.next = new Node();            current = current.next;            current.n = n;            current.previous = last;            last = current;        }        current.next = first;        first.previous = current;        return first;    }    class Node {        int n ;         Node next;        Node previous;    }}