双向单链表
//函数声明：#include"twowaylinklist.h"
#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<stdlib.h>
typedef int ElemType;
typedef struct DulNode
{
struct DulNode *prior;
ElemType data;
struct DulNode *next;
}DulNode;
void judgement_NULL(DulNode *point); //判断动态内存是否开辟成功
DulNode * creat();
void insert(DulNode *head, ElemType x, int i); //在第i个位置上插入一个值为x的结点
void delete_element(DulNode *head, ElemType x); //删除链表中所有的值为x的结点
void delete_place(DulNode *head, int i); //删除第i个结点
void find_element(DulNode *head, int i); //寻找第i个结点上的元素
void find_place(DulNode *head, ElemType x); //寻找所有值为x的结点
void length(DulNode *head);
void output_order(DulNode *head); //正向打印链表
void output_back(DulNode *head); //逆序打印链表
void initslinklist(DulNode *head); //释放整个链表
void sortrank(DulNode *head); //对链表进行排序
int means(); //选择以那种方式进行
#include"twowaylinklist.h"
void judgement_NULL(DulNode *point) //判断开辟动态内存是否成功
{
if (point == NULL)
{
perror("out of memory\n");
exit(EXIT_FAILURE);
}
}
DulNode * creat() //建立链表，以0作为结束标志
{
printf("开始创建：");
ElemType x;
DulNode *head, *r, *p;
head = (DulNode *)malloc(sizeof(DulNode)); //开辟一个头结点
judgement_NULL(head);
head->prior = NULL;
r = head;
while (1)
{
scanf("%d", &x);
if (x != 0)
{
p = (DulNode *)malloc(sizeof(DulNode));
p->data = x;
r->next = p;
p->prior = r;
r = p;
}
else
break;
}
r->next = NULL;
printf("创建成功\n");
return head; //返回头结点的地址
}
void insert(DulNode *head, ElemType x, int i) //在第i个位置上插入一个结点，并且结点的data为x
{
DulNode *p, *r;
p = (DulNode *)malloc(sizeof(DulNode)); //建立这个结点
judgement_NULL(p);
p->data = x;
if (i == 1) //考虑第一个结点的情况
{
p->next = head->next;
head->next->prior = p;
head->next = p;
p->prior = head;
printf("插入成功\n");
}
else
{
r = head->next;
while (r != NULL) //找到这个结点
{
if (i == 1)
break;
r = r->next;
i--;
}
if (r == NULL)
printf("没有这个结点\n");
else //如果这个结点存在
{
r->prior->next = p;
p->prior = r->prior;
p->next = r;
r->prior = p;
printf("插入成功\n");
}
}
}
void delete_element(DulNode *head, ElemType x) //删除链表中所有的X元素
{
DulNode *p, *r;
int flag = 0;
if (head->next == NULL) //考虑链表为空的情况
printf("链表下溢\n");
else
{
p = head->next;
while (p != NULL)
{
if (p->data == x)
{
flag++;
r = p;
p = p->next;
r->prior->next = r->next;
r->next->prior = r->prior;
free(r);
r = NULL;
}
else
p = p->next;
}
if (flag == 0)
printf("没找到该元素\n");
else
printf("共删除%d个\n", flag);
}
}
void delete_place(DulNode *head, int i) //删除指定位置的结点
{
DulNode *p;
if (head->next == NULL)
printf("链表下溢\n");
else
{
p = head->next;
while (p != NULL) //先找到这个位置
{
if (i == 1)
break;
p = p->next;
i--;
}
if (p == NULL)
printf("没有此位置\n");
else
{
p->prior->next = p->next;
p->next->prior = p->prior;
free(p);
p = NULL;
printf("删除成功\n");
}
}
}
void find_element(DulNode *head, int i) //查找第i个结点上的data，找到并输出
{
DulNode *p;
if (head->next == NULL)
printf("链表下溢\n");
else
{
p = head->next;
while (p != NULL)
{
if (i == 1)
break;
p = p->next;
i--;
}
if (p == NULL)
printf("没有该结点\n");
else
printf("结点元素：%d\n", p->data);
}
}
void find_place(DulNode *head, ElemType x) //找到链表中所有data为x的结点，并输出结点位置
{
DulNode *p;
int i = 0;
int flag = 0;
if (head->next == NULL)
printf("链表下溢\n");
else
{
p = head->next;
while (p != NULL)
{
i++;
if (p->data == x)
{
flag++;
printf("此元素的结点位置：%d\n",i);
}
p = p->next;
}
if (flag == 0)
printf("链表中没有该结点\n");
}
}
void length(DulNode *head) //求链表长度
{
DulNode *p = head->next;
int len = 0;
if (head->next == NULL)
printf("链表长度为：%d\n", len);
else
{
while (p != NULL)
{
len++;
p = p->next;
}
printf("链表长度：%d\n", len);
}
}
void output_order(DulNode *head) //正向打印链表
{
DulNode *p = head->next;
if (head->next == NULL)
printf("链表为空");
else
{
printf("顺序打印链表：");
while (p != NULL)
{
printf("%d ", p->data);
p = p->next;
}
}
printf("\n");
}
void output_back(DulNode *head) //反向打印链表
{
DulNode *p;
if (head->next == NULL)
printf("链表为空");
else
{
printf("逆序打印链表：");
p = head->next;
while (p->next != NULL) //让p指向最后一个结点
{
p = p->next;
}
while (p != head)
{
printf("%d ", p->data);
p = p->prior;
}
}
printf("\n");
}
void initslinklist(DulNode *head) //释放当前链表
{
DulNode *p,*r;
p = head;
while (p != NULL)
{
r = p;
p = p->next;
free(r);
r= NULL;
}
head = NULL;
printf("初始化成功\n");
}
void sortrank(DulNode *head)
{
DulNode *p, *r;
p = head->next;
ElemType tmp;
while (p != NULL) //使用冒泡排序
{
r = head->next;
while (r->next != NULL)
{
if ((r->data) > (r->next->data))
{
tmp = r->data;
r->data = r->next->data;
r->next->data = tmp;
}
r = r->next;
}
p = p->next;
}
printf("排序成功\n");
}
int means()
{
int m = 0;
while (1)
{
printf("请选择方式：");
scanf("%d", &m);
if (m == 1 || m == 2)
break;
printf("选择无效，请重新选择\n");
}
return m;
}
//函数测试："twowaylinklist.c"
#include"twowaylinklist.h"
int main()
{
DulNode *ret = NULL;
int n = 0;
int i = 0;
ElemType x;
printf("*********************************************\n");
printf("*********************************************\n");
printf("*1.CreatLinkList 2.Insert *********\n");
printf("*3.Delete 4.Find *********\n");
printf("*5.Length 6.Output *********\n");
printf("*7.InitsLinkLinst 8.Sortrank ********\n");
printf("*0.Exit *********************\n\n\n");
while (1)
{
printf("请选择功能：");
scanf("%d", &n);
if (n == 0) //选择0直接退出
{
free(ret); //退出前先释放列表
exit(1);
}
if (ret == NULL) //如果ret为空，则首先建立链表
{
if (n == 1)
{
printf("创建链表以0作为结束标志\n");
ret = creat();
}
else
printf("请先建立链表\n");
}
else
{
switch (n) //选择剩下的功能
{
case 1: //当ret为空时才能建立链表
printf("当前链表未结束，请先初始化链表\n");
break;
case 2:
printf("请输入要插入的元素和位置：");
scanf("%d", &x);
scanf("%d", &i);
insert(ret, x, i);
break;
case 3:
printf("*1.delete_element 2.delete_place*\n");
if (means() == 1)
{
printf("请输入要删除的元素：");
scanf("%d", &x);
delete_element(ret, x);
}
else
{
printf("请输入要删除的结点：");
scanf("%d", &i);
delete_place(ret, i);
}
break;
case 4:
printf("*1.find_place 2.find_element*\n");
if (means() == 1)
{
printf("请输入要查找的元素：");
scanf("%d", &x);
find_place(ret, x);
}
else
{
printf("请输入要查找的位置：");
scanf("%d", &i);
find_element(ret, i);
}
break;
case 5:
length(ret);
break;
case 6:
printf("*1.output_order 2.output_back*\n");
if (means() == 1)
output_order(ret);
else
output_back(ret);
break;
case 7: //将当前链表释放
initslinklist(ret);
ret = NULL;
break;
case 8:
sortrank(ret);
break;
default:
printf("选择无效，请重新选择\n");
break;
}
}
n = 0;
}
system("pause");
return 0;
}
