双向链表

创建双向循环链表(不带头结点)：

typedef struct DoubleNode{

      int number;
      struct DoubleNode *next;
      struct DoubleNode *prior;
}DoubleNode ,*DoubleList;

DoubleList CreateList(DoubleList head ){

        int SIZE,i=0;
        DoubleList p,q;
        head=(DoubleList)malloc(sizeof(DoubleNode));
        head=NULL;
        p=head;

        cin>>SIZE;
        while(i<SIZE){
            q=(DoubleList)malloc(sizeof(DoubleNode));

            cin>>q->number;
            if(head==NULL){
                head=q;
                p=q;
            }
            else{
                p->next=q;
                q->prior=p;
                p=q;
            }
            i++;
        }
        p->next=head;
       head->prior=p;

        return head;
}
void ShowList(DoubleList head){

     DoubleList p;

     p=head;
     do{
        cout<<p->number<<" ";
        p=p->next;
     }while(p!=head);
}

带头结点:

DoubleList CreateList(DoubleList head ){

        int SIZE,i=0;
        DoubleList p,q;
        head=(DoubleList)malloc(sizeof(DoubleNode));
        p=head;
        cin>>SIZE;
        while(i<SIZE){
            q=(DoubleList)malloc(sizeof(DoubleNode));
            cin>>q->number;
            p->next=q;
            q->prior=p;
            p=q;
            i++;
         }

        p->next=head;
        head->prior=p; //最后的完善部分 带不带头结点都一样

        return head;

}
void ShowList(DoubleList head){

    DoubleList p;

    for(p=head->next;p!=head;p=p->next){
        cout<<p->number<<" ";

    }
}

插入（带头节点）

//这个情况是  这些整数从第二个开始，递增有序  将第一个结点删除并插入链表中的适当位置   就是说白了插入链中和链尾是不一样的
DoubleList   Adjust(DoubleList head){

       DoubleList p,temp,q;
       temp=(DoubleList)malloc(sizeof(DoubleNode));
       temp=head->next;
       head->next=temp->next;
       (head->next)->prior=head;
       p=head->next;
       if(temp->number<head->prior->number){
           for(p;p!=head;p=p->next){
            if(p->number>temp->number){
                q=p->prior;
                p=q->next;
                temp->next=p;
                q->next=temp;
                temp->prior=q;
                p->prior=temp;
                break;
             }
           }
       }
       else{
          temp->next=head;
          temp->prior=head->prior;
          head->prior->next=temp;
          head->prior=temp;
        }
       return head;
}