单链表头插

Linklist insert_head(datatype element,Linklist head)
{//创建新节点
Linklist s=create_node();if(NULL==s)return head;
s->data=element;//1,判断链表为空if(NULL==head){head=s;}else //链表不为空{s->next=head;head=s;}return head;
}

单链表尾插

Linklist insert_rear(datatype element,Linklist head)
{
//创建新节点sLinklist s=create_node();if(NULL==s)return head;s->data=element;//1,判断链表为空if(NULL ==head){head=s;}else //链表不为空{//1,循环到最后一个节点Linklist p=head;while(p->next!=NULL){p=p->next;}//2,在p后面插入sp->next=s;}return head;}

单链表头删

Linklist delete_head(Linklist head)
{//1,判断链表为空if(NULL==head){return head;}else //链表存在1个或多个节点{Linklist del=head;head=head->next;free(del);del=NULL;}return head;
}

 单链表尾删

Linklist delete_rear(Linklist head)
{//1,判断链表为空if(NULL ==head)return head;//2,判断链表只有一个节点if(NULL ==head->next){free(head);head=NULL;}else //存在多个节点>=2{//3.找到倒数第2个节点Linklist del=head;while(del->next->next!=NULL){del=del->next;}//4.删除del->nextfree(del->next);del->next=NULL;}return head;
}

双向链表节点头插

Doublelink double_insert_head(datatype element,Doublelink head)
{//创建新节点sDoublelink s=create_node();if(s==NULL)return head;strcpy(s->data,element);//1.判断链表为空if(NULL ==head)head=s;//2.存在多个节点>=1else{s->next=head;head->priv=s;head=s;}return head;
}

双向链表节点尾插

Doublelink doublelink_insert_rear(datatype element,Doublelink head)
{//创建新节点sDoublelink s=create_node();if(s==NULL)return head;strcpy(s->data,element);//1,没有节点if(NULL ==head)head=s;else{//找到最后一个节点Doublelink p=head;while(p->next!=NULL){p=p->next;}//插入sp->next=s;s->priv=p;}return head;}

双向链表节点头删

Doublelink delete_head(Doublelink head)
{//1,判断链表为空if(NULL==head)return head;//2,存在多个节点Doublelink q=head;head=head->next;if(head!=NULL)head->priv=NULL;free(q);q=NULL;return head;
}

双向链表节点尾删

Doublelink delete_rear(Doublelink head)
{//1,判断链表为空if(NULL ==head)return head;//2,只有一个节点if(head->next==NULL){free(head);head=NULL;}else //>=2{//找到最后一个节点Doublelink p=head;while(p->next!=NULL){p=p->next;}p->priv->next=NULL;free(p);p=NULL;}return head;
}