双向链表的基本操作

main.c

/**2013-11-7*双向链表的基本操作，类似于单向链表，只不过多出了一个前节点指针*基本操作详见代码中*/#include "D_List.h"int main(void){pDLIST pHead = creat_dlist();traverse(pHead);en_dlist(pHead, 3, 8);traverse(pHead);search(pHead, 8);search(pHead, 65);out_dlist(pHead, 5);traverse(pHead);clear(pHead);traverse(pHead);return 0;}

 

以下是D_List.h

#ifndef D_LIST_H#define D_LIST_H#include <stdio.h>#include <malloc.h>#include <stdlib.h>#include <time.h>typedef int ElemType;typedef struct DList   //定义链表结构体{ElemType data;struct DList * prior;struct DList * next;}DLIST, *pDLIST;pDLIST creat_dlist();void en_dlist(pDLIST, int pos, ElemType val);void out_dlist(pDLIST, int pos);bool is_empty(pDLIST);void traverse(pDLIST);int len_dlist(pDLIST);void clear(pDLIST);void search(pDLIST, int);#endif

D_List.cpp

//功能实现#include "D_List.h"pDLIST creat_dlist(){pDLIST head = (pDLIST)malloc(sizeof(DLIST));//创建头节点if (head == NULL){printf("分配内存失败！！！\n");exit(-1);}else{head->prior = head->next = NULL;int n, i;printf("请输入你要创建的节点个数 ：n = ");scanf("%d", &n);srand(time(NULL));pDLIST pNext = NULL;for ( i = 0; i < n; i++){pDLIST pNew = (pDLIST)malloc(sizeof(DLIST));if (NULL == pNew){printf("内存分配失败！！！\n");exit(-1);}else{pNext = head->next;   //保存下一个节点pNew->data = rand()%100;     //放入数据head->next = pNew;    pNew->prior = head;pNew->next = pNext;if(pNext != NULL){pNext->prior = pNew;}}}return head;}}//插入第pos个节点，其中p是移动到了pos-1的位置，这种用法比较好！！void en_dlist(pDLIST pL, int pos, ElemType val){int i = 0;pDLIST p = pL;while (NULL != p && i < pos-1)  //将p指到pos-1所在的位置{i++;p = p->next;}if (i > pos-1 || NULL == p){printf("你插入的节点位置有问题！位置为：pos = %d  ！！\n", pos);return;}else{pDLIST q = p->next;pDLIST pNew = (pDLIST)malloc(sizeof(DLIST));pNew->data = val;p->next = pNew;pNew->prior = p;pNew->next = q;if (q != NULL){q->prior = pNew;}printf("第 %d 个节点 %d 插入成功！！\n", pos, val);return;}}void out_dlist(pDLIST pL, int pos){int i = 0;pDLIST p = pL;while (NULL != p->next && i < pos-1){i++;p = p->next;}if (i > pos-1 || NULL == p->next){printf("你删除的节点不存在！！你要删除的位置为pos = %d \n", pos);return;}else{pDLIST temp = p->next;pDLIST q = temp->next;p->next = q;printf("第 %d 个节点 %d 删除成功！！\n", pos, temp->data);if (q != NULL){q->prior = q;}free(temp);temp = NULL;}}void traverse(pDLIST pL){if (is_empty(pL)){printf("链表为空，不能遍历！！！！！\n");return;}pDLIST p = pL->next;while (p != NULL){printf("%d  ",p->data);p = p->next;}printf("\n");}void search(pDLIST pL, int val){int i = 0 ;int j = 0;pDLIST p = pL->next;while (p != NULL){i++;if (p->data == val){j++;printf("%d 是第 %d 个节点!! \n",val , i);}p = p->next;}if (j == 0){printf("%d不在这个链表中！！\n", val);}}void clear(pDLIST pL){pDLIST p = pL->next;pL->next = NULL;printf("清空链表………\n");while (p != NULL){pDLIST q = p->next;free(p);p = q;}}int len_dlist(pDLIST pL){int len=0;pDLIST p = pL->next;while (NULL != p){len++;p = p->next;}return len;}bool is_empty(pDLIST pL){if (pL->next == NULL && pL->prior == NULL){return true;}else return false;}

测试结果为：