我在约瑟夫斯的比赛中遇到了几个问题。我的第一个问题是我无法弄清楚如何开始计算每轮被淘汰者左侧的人（游戏顺时针方向）。它正确删除，但开始计算被删除人员右侧的人员。我的第二个问题是我无法弄清楚如何打印每一轮被淘汰的人。我大部分都算了算法，但我无法弄清楚这些小细节。任何帮助，将不胜感激！
import java.io.*;
////////////////////////////////////////////////////////////////
class Link
{
public int iData; // data item (key)
public Link next; // next link in list
// -------------------------------------------------------------
public Link(int id) // constructor
{ iData = id; }
// -------------------------------------------------------------
public void display() // display ourself
{ System.out.print(iData + " "); }
} // end class Link
////////////////////////////////////////////////////////////////
class CircList
{
private Link current; // ref to current link
private int count; // # of links on list
// -------------------------------------------------------------
public CircList() // constructor
{
count = 0; // no links on list yet
current = null;
}
// -------------------------------------------------------------
public boolean isEmpty()
{ return count==0; }
// -------------------------------------------------------------
public int getSize()
{ return count; }
// -------------------------------------------------------------
public void insert(int id) // insert after current link
{ // make new link
Link newLink = new Link(id);
if(count == 0) // if first one
{
current = newLink; // current points to it
current.next = current; // next one is us
}
else
{
newLink.next = current.next; // downstream of new link
current.next = newLink; // upstream of new link
}
count++; // one more link
}
// -------------------------------------------------------------
public Link delete() // delete link following currrent
{
Link tempLink;
switch(count)
{
case 0: // current is already null
tempLink = current;
break;
case 1: // delete ourself
tempLink = current;
current = null;
count--;
break;
default: // delete the next one
tempLink = current.next;
current.next = tempLink.next;
count--;
break;
}
return tempLink;
}
// -------------------------------------------------------------
public Link find(int key) // find link with given key
{ // at one past current
int getHome = count;
while(getHome > 0) // while not back to
{ // beginning
if(current.next.iData == key) // found it?
return current.next; // return next one
else // not found
{ // go to next link
current = current.next;
getHome--; // one item closer to home
}
}
return null; // can't find it
}
// -------------------------------------------------------------
public Link delete(int key) // delete link with given key
{
Link nextLink = find(key); // find it
if(nextLink != null) // if found,
{
current.next = nextLink.next; // delete it
count--;
}
return nextLink; // return null or link
}
// -------------------------------------------------------------
public void display() // display the list
{
for(int j=0; j<count; j++)
{
current.next.display();
current = current.next;
}
System.out.println("");
}
// -------------------------------------------------------------
public void step()
{
if(count != 0)
current = current.next; // go to next link
}
// -------------------------------------------------------------
public Link peek()
{ return current.next; }
// -------------------------------------------------------------
} // end class CurcList
////////////////////////////////////////////////////////////////
class CircApp
{
public static void main(String[] args) throws IOException
{
int j, nPlayers, nSkips, startNo;
CircList theList = new CircList(); // make list
putText("Enter the number of players: ");
nPlayers = getInt();
for(j=nPlayers; j>0; j--) // number 10, 20, ...
theList.insert(j);
putText("Players: ");
theList.display();
putText("Enter the the number of spaces to skip: ");
nSkips = getInt();
putText("Enter the the starting player's number: ");
startNo = getInt();
// Add your code here
int m = 1, n;
while(m != startNo)
{
theList.step();
m++;
}
putText("Players: ");
theList.display();
while(theList.getSize() > 1){
n = 0;
while(n != nSkips){
theList.step();
n++;
}
theList.delete();
theList.display();
}
}
// end main()
// -------------------------------------------------------------
public static void putText(String s)
{
System.out.print(s);
System.out.flush();
}
// -------------------------------------------------------------
public static String getString() throws IOException
{
InputStreamReader isr = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isr);
String s = br.readLine();
return s;
}
// -------------------------------------------------------------
public static char getChar() throws IOException
{
String s = getString();
return s.charAt(0);
}
//-------------------------------------------------------------
public static int getInt() throws IOException
{
String s = getString();
return Integer.parseInt(s);
}
// -------------------------------------------------------------
} // end class CircApp
答案 0 :(得分：1)
我希望我能正确理解你 - 你想开始指望被删除的下一个人，而不是之前的人。这样的事情：
public Link delete(int key) // delete link with given key
{
Link nextLink = find(key); // find it
if(nextLink != null) // if found,
{
current.next = nextLink.next; // delete it
current = current.next; //move to the next person
count--;
}
return nextLink; // return null or link
}
关于第二个问题 - 你返回被删除的元素，只需按下这样打印：
Link retVal = theList.delete();
if (retVal != null) {
retVal.display();
}
答案 1 :(得分：1)
显示已删除的播放器非常容易修复。您的delete()方法会返回已删除的Link，因此您只需在返回时使用它即可。而不只是调用theList.delete()使用类似的东西：
theList.delete().display(); //start line
System.out.println("is eliminated"); //finish line
至于从已删除播放器的左侧开始，您需要一种向后移动圆圈的方法。在小圈子中，一种方法是step()比玩家数量少一倍（因为每个玩家踩一次使得围绕圆圈的完整旅行回到当前玩家）。所以在上面的代码添加
for(int i=0; i<theList.getSize()-1; i++)
theList.step();