双向链表的插入、删除、按位置增删改查、栈和队列区别、什么是内存泄漏
2024年2月4日
1.请编程实现双向链表的头插，头删、尾插、尾删
头文件：
#ifndef __HEAD_H__
#define __HEAD_H__
#include
#include
#include
typedef int datatype;
enum{FALSE=-1,SUCCSE};
typedef struct Node
{
datatype data;
struct Node *next;
struct Node *prev;
}*Doublelist;
Doublelist create();
Doublelist insert_head(Doublelist head,datatype element);
Doublelist insert_rear(Doublelist head,datatype element);
void output(Doublelist head);
Doublelist delete_head(Doublelist head);
Doublelist delete_rear(Doublelist head);
#endif
主函数：
#include"head.h"
int main(int argc, const char *argv[])
{
Doublelist head=NULL;
int n;
printf("please enter n:");
scanf("%d",&n);
datatype element;
for(int i=0;i自定义函数：
#include"head.h"
/*
* function: 节点创建
* @param [ in]
* @param [out] 成功返回首地址，失败返回空
* @return
*/
Doublelist create()
{
Doublelist s=(Doublelist)malloc(sizeof(struct Node));
if(s==NULL)
return NULL;
s->data=0;
s->next=s->prev=NULL;
return s;
}
/*
* function: 头插
* @param [ in] 头 插入元素
* @param [out] 头
* @return
*/
Doublelist insert_head(Doublelist head,datatype element)
{
Doublelist s=create();
s->data=element;
if(NULL==head)
head=s;
else
{
s->next=head;
head->prev=s;
head=s;
}
return head;
}
/*
* function: 尾插
* @param [ in] 头 插入元素
* @param [out] 头
* @return
*/
Doublelist insert_rear(Doublelist head,datatype element)
{
Doublelist s=create();
s->data=element;
if(NULL==head)
head=s;
else
{
Doublelist p=head;
while(p->next)
p=p->next;
p->next=s;
s->prev=p;
}
return head;
}
/*
* function: 遍历输出
* @param [ in] 头
* @param [out]
* @return
*/
void output(Doublelist head)
{
if(head==NULL)
{
puts("empty");
return;
}
Doublelist p=head;
while(p)
{
printf("%-5d",p->data);
p=p->next;
}
}
/*
* function: 头删
* @param [ in] 头
* @param [out] 头
* @return
*/
Doublelist delete_head(Doublelist head)
{
if(head==NULL)
return NULL;
if(head->next==NULL)
{
free(head);
head=NULL;
return NULL;
}
Doublelist del=head;
head=head->next;
free(del);
head->prev=NULL;
del=NULL;
return head;
}
/*
* function: 尾删
* @param [ in] 头
* @param [out] 头
* @return
*/
Doublelist delete_rear(Doublelist head)
{
if(NULL==head)
return head;
if(head->next==NULL)
{
free(head);
head=NULL;
return NULL;
}
Doublelist p=head;
while(p->next)
p=p->next;
Doublelist del=p;
p->prev->next=NULL;
free(del);
del=NULL;
return head;
}
头插、头删、尾删：
尾插、头删、尾删：
⒉请编程实现双向链表按任意位置插入、删除、修改、查找
头文件：
#ifndef __HEAD_H__
#define __HEAD_H__
#include
#include
#include
typedef int datatype;
enum{FALSE=-1,SUCCSE};
typedef struct Node
{
datatype data;
struct Node *next;
struct Node *prev;
}*Doublelist;
Doublelist create();
Doublelist insert_head(Doublelist head,datatype element);
Doublelist insert_rear(Doublelist head,datatype element);
void output(Doublelist head);
Doublelist delete_head(Doublelist head);
Doublelist delete_rear(Doublelist head);
Doublelist insert_pos(Doublelist head,int pos,datatype element);
Doublelist delete_pos(Doublelist head,int pos);
void find_pos(Doublelist head,int pos);
int revise_pos(Doublelist head,int pos,datatype element);
#endif
主函数：
#include"head.h"
int main(int argc, const char *argv[])
{
Doublelist head=NULL;
int n;
printf("please enter n:");
scanf("%d",&n);
datatype element;
for(int i=0;i自定义函数：
#include"head.h"
/*
* function: 节点创建
* @param [ in]
* @param [out] 成功返回首地址，失败返回空
* @return
*/
Doublelist create()
{
Doublelist s=(Doublelist)malloc(sizeof(struct Node));
if(s==NULL)
return NULL;
s->data=0;
s->next=s->prev=NULL;
return s;
}
/*
* function: 头插
* @param [ in] 头 插入元素
* @param [out] 头
* @return
*/
Doublelist insert_head(Doublelist head,datatype element)
{
Doublelist s=create();
s->data=element;
if(NULL==head)
head=s;
else
{
s->next=head;
head->prev=s;
head=s;
}
return head;
}
/*
* function: 尾插
* @param [ in] 头 插入元素
* @param [out] 头
* @return
*/
Doublelist insert_rear(Doublelist head,datatype element)
{
Doublelist s=create();
s->data=element;
if(NULL==head)
head=s;
else
{
Doublelist p=head;
while(p->next)
p=p->next;
p->next=s;
s->prev=p;
}
return head;
}
/*
* function: 遍历输出
* @param [ in] ｔｏｕ
* @param [out]
* @return
*/
void output(Doublelist head)
{
if(head==NULL)
{
puts("empty");
return;
}
Doublelist p=head;
while(p)
{
printf("%-5d",p->data);
p=p->next;
}
}
/*
* function: 头删
* @param [ in] 头
* @param [out] 头
* @return
*/
Doublelist delete_head(Doublelist head)
{
if(head==NULL)
return NULL;
if(head->next==NULL)
{
free(head);
head=NULL;
return NULL;
}
Doublelist del=head;
head=head->next;
free(del);
head->prev=NULL;
del=NULL;
return head;
}
/*
* function: 尾删
* @param [ in] 头
* @param [out] 头
* @return
*/
Doublelist delete_rear(Doublelist head)
{
if(NULL==head)
return head;
if(head->next==NULL)
{
free(head);
head=NULL;
return NULL;
}
Doublelist p=head;
while(p->next)
p=p->next;
Doublelist del=p;
p->prev->next=NULL;
free(del);
del=NULL;
return head;
}
/*
* function: 计算长度
* @param [ in] 头
* @param [out] 长度
* @return
*/
int lengh(Doublelist head)
{
int len=0;
while(head)
{
len++;
head=head->next;
}
return len;
}
/*
* function: 按任意位置插入
* @param [ in] 头 位置 插入元素
* @param [out] 头
* @return
*/
Doublelist insert_pos(Doublelist head,int pos,datatype element)
{
if(NULL==head || pos<1 || pos>lengh(head)+1)
{
puts("POS ERROR OR EMPTY");
return head;
}
if(pos==1)
{
head=insert_head(head,element);
return head;
}
else if(pos==lengh(head)+1)
{
head=insert_rear(head,element);
return head;
}
Doublelist s=create();
s->data=element;
Doublelist p=head;
for(int i=1;inext;
s->next=p->next;
p->next->prev=s;
s->prev=p;
p->next=s;
return head;
}
/*
* function: 任意位置删除
* @param [ in] 头 位置
* @param [out] 头
* @return
*/
Doublelist delete_pos(Doublelist head,int pos)
{
if(NULL==head || pos<1 || pos>lengh(head))
{
puts("POS ERROR OR EMPTY");
return head;
}
if(pos==1)
head=delete_head(head);
else if(pos==lengh(head))
head=delete_rear(head);
else
{
Doublelist p=head;
for(int i=1;inext;
Doublelist del=p->next;
p->next=del->next;
del->next->prev=p;
free(del);
del=NULL;
}
return head;
}
/*
* function: 任意位置查找
* @param [ in] 头 位置
* @param [out]
* @return
*/
void find_pos(Doublelist head,int pos)
{
if(NULL==head || pos<1 || pos>lengh(head))
{
puts("POS ERROR OR EMPTY");
return;
}
Doublelist p=head;
for(int i=1;inext;
printf("The pos element is %d\n",p->data);
}
/*
* function: 任意位置修改
* @param [ in] 头 位置 修改后的元素
* @param [out] 成功返回０，失败返回－１
* @return
*/
int revise_pos(Doublelist head,int pos,datatype element)
{
if(NULL==head || pos<1 || pos>lengh(head))
{
puts("POS ERROR OR EMPTY");
return FALSE;
}
Doublelist p=head;
for(int i=1;inext;
p->data=element;
return SUCCSE;
}
任意位置插入：
任意位置删除：
任意位置查找：
任意位置修改：
3.请简述栈和队列的区别?
1、栈和队列的出入方式不同：栈是先进后出，队列是先进先出。
2、栈和队列的实现时操作位置不同：栈是出入在一端，后入先出，队列是出入在两端先进先出。
4.请简述什么内存泄露?
程序员释放在堆区申请的内存时，指针未指向释放内存的首地址，导致前部分内存未释放，且没有指针指向导致内存泄漏。