约瑟夫环（循环单链表）

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

const int maxn = 1000;
int Num_of_Player;
int m_val;
int cnt;
//循环链表
typedef struct LNode
{
    int num, password;
    struct LNode *next;
}*linklist, lnode;

void InitLinkList(linklist *L)
{
    (*L) = (linklist)malloc(sizeof(lnode));
    (*L)->num = -1;
    (*L)->password = -1;
    (*L)->next = *L;
}

void ClearLinkList(linklist *L)
{
    lnode *pos, *node;

    pos = (*L)->next;
    while(pos != (*L))
    {
        node = pos;
        pos = pos->next;
        free(node);
    }
    (*L)->next = (*L);
}

void CreatLinkList(linklist L)
{
    lnode *u, *v;
    //清空链表
    ClearLinkList(&L);
    //初始化尾指针
    v = L;
    int j = 1, psw;

    printf("please input the number of the players: ");
    scanf("%d", &Num_of_Player);
    printf("
please input the passwords of the players: ");
    while(j <= Num_of_Player)
    {
        scanf("%d", &psw);
/*----------------------插入新结点-------------------------------------*/
        u = (linklist)malloc(sizeof(lnode));     //分配一个节点head
        u->num = j;                              //为结点赋值
        u->password = psw;
        v->next = u;
        v = u;                                //更新尾结点
/*---------------------------------------------------------------------*/
        j++;
    }
    v->next = L;
}

void DestoryLinkList(linklist L)
{
    ClearLinkList(&L);//清空链表
    free(L);//销毁虚拟头结点
}

void solve(linklist L)
{
    printf("please input the value of m: ");
    scanf("%d", &m_val);

    lnode *u, *v;
    v = L;
    int k = 0;
    while(v->next != v)
    {
        u = v;
        v = v->next;

        //注意：如果到了头部的虚拟结点，则再向后移一步
        if(v == L)
        {
            u = v;
            v = v->next;
        }
        k++;

        if(k == m_val)
        {
//            cout << m_val << endl;
            //输出并释放掉第m个结点
            if(cnt) printf(" ");
            printf("%d", v->num);
            m_val = v->password;
/*----------------销毁第m个数-----------------*/
            u->next = v->next;
            lnode *tmp = v;
            free(tmp);
            v = u;
/*----------------销毁第m个数-----------------*/
            k = 0;
            cnt++;
        }
    }
}


int main()
{
    linklist players;//开始“游戏”
    InitLinkList(&players);//初始化“游戏人员”
    CreatLinkList(players);//创建“游戏人员”
    solve(players);//进行“游戏”
    DestoryLinkList(players);//销毁“游戏人员”
    return 0;
}