用结构体创建链表和用类创建链表

当要保存和管理的数据元素的数目变化很大时，使用链表效率会很高。在链表每个元素都保存在节点：

                  node 1          node 2                node n

head--->元素1   -->元素2..........元素n<----tail

            next          next              NULL

用结构体实现：

#include"15.h"struct stu{  char name[22];  int age;  stu *next;};  int main(){  char name[22];  int age;  stu c={"ccc",20,NULL};  stu c1={"bbb",21,&c};  stu b={"bbb",24,&c1};  stu a={"aaa",27,&b};  stu *p,*head=&a,*before=NULL;//链表的创建  int f=0,k=0;  p=head;  cout<<"the inf of stu:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}  cout<<endl;  p=head;  cout<<"enter the name you want:"<<endl;  cin>>name;  while(p!=NULL){ f=0;  if(strcmp(name,p->name)==0) {f=1;k++;}  if(f==1)cout<<" the name:"<<p->name<<" the age:"<<p->age<<endl;  p=p->next;}//结构链表的查询  if(k==0)  cout<<"no use!"<<endl;  cout<<endl;  p=head;  cout<<"enter enter the age of add,and it will added by age:"<<endl;  cin>>age;  stu add={"add",age,NULL};  while(p!=NULL){  if(age>p->age) break;       before=p;   p=p->next;}  if(before==NULL)  {add.next=head;head=&add;}//最大，在表头插入  else {add.next=before->next;before->next=&add;}//在表内部插入  p=head; cout<<"the inf of stu after adding:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}  cout<<endl;  p=head;  before=NULL;  cout<<"enter the name you delete:"<<endl;  cin>>name;  while(p!=NULL){  f=0,k=0;  if(strcmp(name,p->name)==0) {f=1;k++;break;}  before=p;  p=p->next;}  if(f==1)//含有该数据进行删除   {  if(before==NULL){head=p->next;}//在表头删除  else {before->next=p->next;}//在表中删除  }  if(k==0)  {cout<<"no use!"<<endl;  p=head; cout<<"the inf of stu after no deleted:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}}  else{ p=head; cout<<"the inf of stu after deleted:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}}  cout<<endl;  p=head;  before=NULL;  system("pause");  return 0;}

在结构体实现的链表里，实现了查找，插入，删除等常用操作。

而类实现：

class stu{public:char name[22];int age;stu *next;//改成可以访问stu(){next=NULL;}stu(char *p,int age,stu *add){strcpy(name,p);//注意不要name=pthis->age=age;next=add;}};

int main(){  char name[22];  int age; stu *head,*before=NULL,*p;stu c("ccc",20,NULL);stu c1("bbb",21,&c);stu b("bbb",24,&c1);stu a("aaa",27,&b);head=&a;p=head;int f=0,k=0;  cout<<"the inf of stu:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}  cout<<endl;  p=head;  cout<<"enter the name you want:"<<endl;  cin>>name;  while(p!=NULL){  f=0;  if(strcmp(name,p->name)==0){f=1;k++;}  if(f==1)cout<<" the name:"<<p->name<<" the age:"<<p->age<<endl;  p=p->next;}//结构链表的查询  if(k==0)  cout<<"no use!"<<endl;  cout<<endl;  p=head;  cout<<"enter enter the age of add,and it will added by age:"<<endl;  cin>>age;  stu add("add",age,NULL);  while(p!=NULL){  if(age>p->age)  break;  before=p;  p=p->next;}if(before==NULL)  {add.next=head;head=&add;}//最大，在表头插入    else {add.next=before->next;before->next=&add;}//在表内部插入  p=head; cout<<"the inf of stu after adding:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}  cout<<endl;  p=head;  before=NULL;  cout<<"enter the name you delete:"<<endl;  cin>>name;  while(p!=NULL){  f=0,k=0;  if(strcmp(name,p->name)==0) {f=1;k++;break;}  before=p;  p=p->next;}  if(f==1)//含有该数据进行删除   {  if(before==NULL){head=p->next;}//在表头删除  else {before->next=p->next;}//在表中删除  }  if(k==0)  {cout<<"no use!"<<endl;  p=head; cout<<"the inf of stu after no deleted:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}}  else{ p=head; cout<<"the inf of stu after deleted:"<<endl;  while(p!=NULL){  cout<<"the name:"<<p->name<<" the age: "<<p->age<<" the next:"<<endl;  p=p->next;}}  cout<<endl;  p=head;  before=NULL;  system("pause");  return 0;}