poj3750约瑟夫环，循环队列

Description

有N个小孩围成一圈，给他们从1开始依次编号，现指定从第W个开始报数，报到第S个时，该小孩出列，然后从下一个小孩开始报数，仍是报到S个出列，如此重复下去，直到所有的小孩都出列（总人数不足S个时将循环报数），求小孩出列的顺序。

Input

第一行输入小孩的人数N（N<=64）

接下来每行输入一个小孩的名字(人名不超过15个字符)

最后一行输入W,S (W < N)，用逗号”,”间隔

Output

按人名输出小孩按顺序出列的顺序，每行输出一个人名

Sample Input

5

Xiaoming

Xiaohua

Xiaowang

Zhangsan

Lisi

2,3

Sample Output

Zhangsan

Xiaohua

Xiaoming

Xiaowang

Lisi

import java.io.BufferedInputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {

public static void main(String[] args) {

Scanner cin = new Scanner( new BufferedInputStream(System.in) )  ;
PrintWriter cout = new PrintWriter(System.out)  ;

List<String> answer = new Solve(cin.nextInt() , cin).todo() ;

for(String name : answer){
cout.println(name) ;
}

cout.flush() ;
cout.close() ;

}

}

class Node{
String name ;
Node pre , next ;
Node(){
pre = next = null  ;
}
}

class Solve{

Node head ;
int  w  , s  ;

public Solve(int n , Scanner cin) {
make(n) ;
Node now = head ;
for(int i = 1 ; i <= n ; i++){
now.name = cin.next() ;
now = now.next ;
}
String[] p = cin.next().split(",") ;
w =  Integer.parseInt(p[0]) ;
s =  Integer.parseInt(p[1]) ;
}

void  make(int n){
head = new Node() ;
Node now = head ;
for(int i = 1 ; i < n ; i++){
now.next = new Node() ;
now.next.pre = now ;
now = now.next ;
}
now.next = head ;
head.pre = now ;
}

Node move(Node now , int step){
for(int i = 1 ; i <= step ; i++)
now = now.next ;
return now ;
}

Node delete(Node now){
now.next.pre = now.pre ;
now.pre.next = now.next ;
return now.next ;
}

List<String>  todo(){

List<String> answer = new ArrayList<String>() ;

Node now = move(head , w-1) ;
while(now.next != now){
now = move(now, s-1) ;
answer.add(now.name) ;
now = delete(now) ;
}
answer.add(now.name) ;

return answer ;
}

}