约瑟夫问题解答

问题：
编号为1,2，····n的n个人按顺时针做成一圈，一开始任选一个正整数作为报数的上限值m，从第一个人开始按顺时针方向自1开始顺时针报数，报到m时停止，这个人出列。从他在顺时针方向上的下一个人开始重新报数，如此下去，直至所有人出列。

下面是用STL中的list

#include <iostream>#include <list>#include <algorithm>using namespace std;int main(){    int i, m = 6,n=20;    list<int> ilist;    //下面是用链表解决约瑟夫环问题    for (i = 1; i <= 20; i++)        ilist.push_back(i);    cout << "size= " << ilist.size() << endl;    list<int> ::iterator ite;    for (ite = ilist.begin(); ite != ilist.end(); ++ite)        cout << *ite << ' ';    cout << endl;    //m %= n;这是错误的    list<int>::iterator pit= ilist.begin();    while (!ilist.empty())    {        int i = 1;        for (; i < m; i++)            if (++pit == ilist.end())                pit = ilist.begin();        printf("%d ", *pit);        if((pit=ilist.erase())==ilist.end())                      pit = ilist.begin();       //cout << *(pit)<<endl;       }      system("pause");}

//用自己的循环链表解决

#include < iostream>#include <vector>#include <algorithm>#include <string>#include <climits>using namespace std;struct node {    int data;    node* next;    node() { data = 0; next = nullptr; }    node(int x) { data = x; next = nullptr; }};//下面是约瑟夫问题（循环链表的操作）node* node_creat(int n){    node* pRet = nullptr;    if (n != 0)    {        int n_idx = 1;        node* p_node = nullptr;        p_node=new node[n];        if (NULL==p_node )        {            return nullptr;        }        pRet=p_node;        while (n_idx < n)        {            p_node->data = n_idx;            p_node->next = p_node + 1;            p_node = p_node->next;            n_idx++;        }        p_node->data = n;        p_node->next = pRet;    }    return pRet;}void Josephus(){    node* pList = NULL, *pIter = NULL;    int n = 20, m = 6;    pList = node_creat(n);    pIter = pList;    m %= n;    while (pIter != pIter->next)    {        int i = 1;        for (; i < m - 1; i++)        {            pIter = pIter->next;        }        //输出第m个节点        printf("%d ", pIter->next->data);        pIter->next = pIter->next->next;        pIter = pIter->next;    }    printf("%d\n", pIter->data);    delete []pList;//不要忘记释放内存}int main() {    Josephus();}