SDUTOJ-2054 数据结构实验之链表九：双向链表

 题目链接

#include <iostream>
#include <cstdlib>

using namespace std;

typedef int ElementType;

typedef struct node
{
    ElementType x;
    struct node * next;
    struct node * front;
} Lnode;

typedef Lnode * List;




int main()
{
    int n, m;
    cin>>n>>m;
    List head = (List) malloc( sizeof(Lnode) );
    head->next = NULL;
    head->front = NULL;

    List tail = head;
    for(int i = 0; i < n; i++)
    {
        List p = (List) malloc( sizeof(Lnode) );
        cin>>p->x;
        p->front = tail;
        tail = tail->next = p;
    }
    tail->next = NULL;

    int t;
    for(int i = 0; i < m; i++)
    {
        cin>>t;
        List p = head->next;
        while(p && p->x != t) p = p->next;
        if(p)
        {
            if(p->front != head || p->next)
            {
                if(p->front != head && p->next)
                {
                    cout<<p->front->x<<' '<<p->next->x<<endl;
                }
                else if(p->front != head)
                {
                    cout<<p->front->x<<endl;
                }
                else
                {
                    cout<<p->next->x<<endl;
                }

            }
        }
    }
    return 0;
}