十四周任务（二）

#include<iostream>
using namespace std;

class Student
{
public:
Student(int n,double s){num=n;score=s;next=NULL;}
Student *next;
int num;
double score;
};

class MyList
{
public:
MyList(){head=NULL;}
MyList(int n,double s){head=new Student(n,s);} //以Student(n,s)作为单结点的链表
int display();   //输出链表，返回值为链表中的结点数
void insert(int n,double s);   //插入：将Student(n,s)结点插入链表，该结点作为第一个结点
void append(int n,double s);   //追加：将Student(n,s)结点插入链表，该结点作为最后一个结点
void cat(MyList &il);  //将链表il连接到当前对象的后面
int length();   //返回链表中的结点数
private:
Student *head;
};
int MyList::display ()
{
if (head=NULL)
{
cout<<"empty\n";
return  0;
}
int c=0;
Student *pt=head;
while(pt)
{++c;
cout<< pt->num<< " " << pt->score<<endl;
pt = pt->next;
}
return c;
}
void MyList::insert  (int n,double s )

{
Student * pt=new Student(n,s);
pt-> next=head;
head=pt;
}
void MyList:: append (int n, double s)
{
Student * pt =new Student (n,s);
if (head==NULL)
head=pt ;
else
{
Student*pts=head;
Student *pte=pts->next ;
while (pte)
{
pts=pte;
pte=pts->next ;
}
pts->next =pt;
}
}

void MyList::cat (MyList &il)
{
Student *pt=il.head ;
while (pt)
{
append (pt->num,pt->score );
pt=pt->next ;
}
}
int MyList ::length ()
{
int c=0;
Student *pt =head;
while (pt)
{
++c;
pt=pt->next ;
}
return c;
}

int main()
{
int n;
double s;
MyList head1;
cout<<"input head1: "<<endl;  //输入head1链表
for(int i=0;i<3;i++)
{
cin>>n>>s;
head1.insert(n,s);  //通过“插入”的方式
}
cout<<"head1: "<<endl; //输出head1
head1.display();

MyList head2(1001,98.4);  //建立head2链表
head2.append(1002,73.5);  //通过“追加”的方式增加结点
head2.append(1003,92.8);
head2.append(1004,99.7);
cout<<"head2: "<<endl;   //输出head2
head2.display();

head2.cat(head1);   //反head1追加到head2后面
cout<<"length of head2 after cat: "<<head2.length()<<endl;
cout<<"head2 after cat: "<<endl;   //显示追加后的结果
head2.display();

system("pause");
return 0;
}