比如：1(头)->2->2->3->3->1->1(头) 去除以后的结果是1->2->3，注意头尾的1也要去掉一个。

#include "stdafx.h"#include 
     
      using namespace std;struct tnode{    tnode* next;    int value;};tnode* unique(tnode *head){    tnode* p = head;    while (p->next != head)    {        if (p->next->value == p->value)        {            tnode* temp = p->next;            p->next = temp->next;            delete temp;        }        else        {            p = p->next;        }    }    if (p->value == head->value)    {        p->next = head->next;        delete head;        head = p;    }    return head;};void print(tnode* head){    tnode* i = head;    while (i->next != head)    {        cout << i->value << " ";        i = i->next;    }    cout << i->value << endl;}int _tmain(int argc, _TCHAR* argv[]){    tnode* node1 = new tnode;    node1->value = 1;    tnode* node2 = new tnode;    node2->value = 1;    tnode* node3 = new tnode;    node3->value = 2;    tnode* node4 = new tnode;    node4->value = 2;    tnode* node5 = new tnode;    node5->value = 3;    tnode* node6 = new tnode;    node6->value = 1;    node1->next = node2;    node2->next = node3;    node3->next = node4;    node4->next = node5;    node5->next = node6;    node6->next = node1;    tnode* head = unique(node1);    print(head);    return 0;}