C语言实现双链表基本操作（创建、查找、插入、删除）

//双链表基本操作

#include<stdio.h>

#include<stdlib.h>

typedef int ElemType;

typedef struct DNode

{

ElemType data;

struct DNode *prior,*next;

}DNode,*DLinkList;

//尾插法建立链表

DLinkList CreatDList(DLinkList &la)

{

int x;

la = (DLinkList)malloc(sizeof(DNode));

la->next = NULL;

DNode *s,*r=la;

scanf("%d",&x);

while(x!=9999)

{

s = (DNode *)malloc(sizeof(DNode));

s->data = x;

r->next = s;

s->prior = r;
//连接前驱

r = s;

scanf("%d",&x);

}

r->next = NULL;

return la;

}

//按序号查找节点

DNode *GetDElem(DLinkList L,int i)

{

int j = 1;

DNode *p = L->next;

if(i<1)

return NULL;

while(p&&j<i)

{

p = p->next;

j++;

}

return p;

}

//双链表的插入操作

DNode *InsertDElem(DLinkList L,int x,int i)

{

DNode *p = GetDElem(L,i);

DNode *s = (DNode*)malloc(sizeof(DNode));

s->data = x;

s->next = p->next;

p->next->prior = s;

s->prior = p;

p->next = s;

return p;

}

//双链表的删除操作

DNode *DeleteDElem(DLinkList L,int i)

{

DNode *p = GetDElem(L,i-1);

DNode *q = p->next;

p->next = q->next;

q->next->prior = p;

free(q);

return p;

}

void main()

{

DLinkList la;

DNode *m;

CreatDList(la);

//m = InsertDElem(la,54,3);

m = DeleteDElem(la,3);

printf("%d,%d,%d\n",m->prior->data,m->data,m->next->data);

}