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// linked list
#include<string>
#include<iostream>
using namespace std;
class student{
private:
string name;
int grade;
student* next;
public:
//constructor and destructor and copy
student(){
name='\0';
grade=0;
next=NULL;
}
student(string name_, int grade_){
name=name_;
grade=grade_;
next=NULL;
}
//destruc
~student(){
name='\0';
grade=0;
next=NULL;
}
//copy and overloading
student(student& sv){
this->name= sv.name;
this->grade=sv.grade;
this->next=sv.next;//(*this)=sv;
}
student*& getnext(){
return next;
}
string& getname(){
return name;
}
int& getgrade(){
return grade;
}
student& operator = (student& sv2 );
friend bool operator ==(student& sv1, student& sv2);
friend double operator +(student& sv1, student& sv2);
friend istream& operator >>(istream& input, student& sv);
friend ostream& operator <<(ostream& output, student& sv);
};
bool operator ==(student& sv1, student& sv2){
if(sv1.grade!= sv2.grade) return false;
else return true;
}
double operator +(student& sv1, student& sv2){
double temp;
temp=sv1.grade+sv2.grade;
return temp;
}
istream& operator >>(istream& input, student& sv){
cout<<"name: ";
getline(input, sv.name);
cout<<"grade: ";
input>>sv.grade;
sv.next= NULL;
}
ostream& operator <<(ostream& output, student& sv){
cout<<"name: "<<sv.name<<endl<<"grade: "<<sv.grade<<endl;
}
class linklist{
private:
student *first, *last;
public:
student* getfirst(){
return first;
}
linklist();
~linklist();
void clear(){
student* temp=first;
while(temp!=NULL){
first=first->getnext();
delete temp;
temp=first;
//temp=first;
//first=first->getnext();
//delete temp;
}
if(first==NULL) cout<<"empty 1";
first=last=NULL;
}
void remove();
void sort();
void search();
//nhap du lieu, toan tu viet trong
friend istream& operator >>(istream& input, linklist& ll);
friend ostream& operator <<(ostream& output, linklist& ll);
};
linklist::linklist(){
first=last=NULL;
}
linklist::~linklist(){
clear();
}
void linklist::remove(){
string name;
cout<<"which's name you want to remove : ";
cin>>name;
if(name==this->first->getname()){
student* temp;
temp=this->first;
this->first=this->first->getnext();
delete temp;
}
else{
student *pre, *after, *cur;
for(pre=this->first;pre->getnext()!=NULL; pre=pre->getnext()){
cur=pre->getnext();
after=cur->getnext();
if(name==cur->getname()){
pre->getnext()=after;
delete cur;
}
if(pre->getnext()==NULL) break;
}
if(after==NULL){
this->last=pre;
}
}
}
istream& operator >>(istream& input, linklist& ll){
char yorn;
while(1){
cout<<"fill in the information(y/n): ";
input>>yorn;
input.ignore(1);
if(yorn!= 'y'&& yorn !='Y') break;
student *temp= new student;
input>>(*temp);
if(ll.first==NULL){
ll.first= ll.last= temp;
}
else {
ll.last->getnext()= temp;
ll.last=temp;
}
}
ll.last->getnext()=NULL;
return input;
}
ostream& operator <<(ostream& output, linklist& ll){
student *cur;
cur=ll.first;
if(ll.first==NULL) cout<<"empty 2";
else{
for(cur= ll.first; cur!=NULL; cur=cur->getnext()){
output<<cur->getname();
output<<" "<<cur->getgrade();
cout<<endl;
}
}
return output;
}
int main(){
linklist *ll= new linklist;
cin>>(*ll);
ll->remove();
cout<<(*ll);
cin>>(*ll);
cout<<(*ll);
delete ll;
if(ll->getfirst()==NULL) cout<<"empty 3";
cout<<(*ll);
return 0;
}
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