第7、8、9、10、11、12题

<img src="http://img.blog.csdn.net/20150420224654282" alt="" />7.(1) #include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}void change(int n,float s){num=n;score=s;}//void display()void display()const{ cout<<num<<" "<<score<<endl;}private:int num;float score;};int main(){ //Student stud(101,78.5); const Student stud(101,78.5); stud.display(); //stud.change(101,80.5); //stud.display(); return 0;}

<img src="http://img.blog.csdn.net/20150420224154075" alt="" />

(2) #include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}//void change(int n,float s)void change(int n,float s)const{num=n;score=s;}//void display()void display()const{ cout<<num<<" "<<score<<endl;}private://int num;mutable int num;//float score;mutable float score;};int main(){ //Student stud(101,78.5); const Student stud(101,78.5); stud.display(); stud.change(101,80.5); stud.display(); return 0;}

<img src="http://img.blog.csdn.net/20150420224115583" alt="" />

(3) #include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}void change(int n,float s){num=n;score=s;}void display(){ cout<<num<<" "<<score<<endl;}private:int num;float score;};int main(){ Student stud(101,78.5); Student *p=&stud; p->display(); p->change(101,80.5); p->display(); return 0;}

<img src="http://img.blog.csdn.net/20150420224131152" alt="" />(4) #include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}//void change(int n,float s)void change(int n,float s)const{num=n;score=s;}//void display()void display()const{ cout<<num<<" "<<score<<endl;}private://int num;mutable int num;//float score;mutable float score;};int main(){ //Student stud(101,78.5); const Student stud(101,78.5); stud.display(); const Student *p = &stud; //stud.change(101,80.5); p->change(101,80.5); //stud.display(); p->display(); return 0;}

<img src="http://img.blog.csdn.net/20150420224201868" alt="" />

(5)#include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}//void change(int n,float s)void change(int n,float s)const{num=n;score=s;}//void display()void display()const{ cout<<num<<" "<<score<<endl;}private://int num;mutable int num;//float score;mutable float score;};int main(){ //Student stud(101,78.5); const Student stud(101,78.5); stud.display(); const Student *p = &stud; //stud.change(101,80.5); p->change(101,80.5); //stud.display(); p->display(); return 0;}

<img src="http://img.blog.csdn.net/20150420224502164" alt="" />

(5)#include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}//void change(int n,float s)void change(int n,float s)const{num=n;score=s;}//void display()void display() const{ cout<<num<<" "<<score<<endl;}private://int num;mutable int num;//float score;mutable float score;};int main(){ //Student stud(101,78.5); const Student stud(101,78.5); stud.display(); //const Student *p = &stud; Student * const p=&stud; //stud.change(101,80.5); //p->change(101,80.5); //stud.display(); p->display(); return 0;}

8. #include <iostream>using namespace std;class Student{public:Student(int n,float s):num(n),score(s){}void change(int n,float s){ num=n; score=s;}void display(){ cout<<num<<" "<<score<<endl;}private:int num;float score;};int main(){ Student stud(101,78.5); void fun(Student &); fun(stud); return 0;}void fun(Student &stu){ stu.display(); stu.change(101,80.5); stu.display();}

<img src="http://img.blog.csdn.net/20150420224533864" alt="" />

9. #include <iostream>using namespace std;class Product{public:Product(int n,int q,float p):num(n),quantity(q),price(p){}void total();static float average();static void display();private:int num;int quantity;float price;static float discount;static float sum;static int n;};void Product::total(){ float rate=1.0; if(quantity>10) rate=rate*0.98; sum=sum+quantity*price*rate*(1-discount); n=n+quantity;}void Product::display(){ cout<<sum<<endl; cout<<average()<<endl;}float Product::average(){ return (sum/n);}float Product::discount=0.05;float Product::sum=0.0;int Product::n=0;int main(){Product prod[3]={Product(101,5,23.5),Product(102,12,24.56),Product(103,100,21.5)};for(int i=0;i<3;i++)prod[i].total();Product::display();return 0;}

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10. #include <iostream>using namespace std;class Date;class Time{public:Time(int ,int ,int );friend void display(const Date &,const Time &);private:int hour;int minute;int sec;};Time::Time(int h,int m,int s){ hour=h; minute=m; sec=s;}class Date{public:Date(int ,int ,int );friend void display(const Date &,const Time &);private:int day;int month;int year;};Date::Date(int d,int m,int y){ day=d; month=m; year=y;}void display(const Date &d,const Time &t){ cout<<d.day<<" "<<d.month<<" "<<d.year<<endl; cout<<t.hour<<" "<<t.minute<<" "<<t.sec<<endl;}int main(){ Time t(10,13,56); Date d(10,25,2004); display(d,t); return 0;}

<img src="http://img.blog.csdn.net/20150420224654282" alt="" />

11.#include <iostream>using namespace std;class Time;class Date{public:Date(int ,int ,int);friend Time;private:int day;int month;int year;};Date::Date(int d,int m,int y){ int day=d; int month=m; int year=y;}class Time{public:Time(int,int,int);void display(const Date &);private:int hour;int minute;int sec;};Time::Time(int h,int m,int s){ hour=h; minute=m; sec=s;}void Time::display(const Date &d){ cout<<d.day<<" "<<d.month<<" "<<d.year<<endl; cout<<hour<<" "<<minute<<" "<<sec<<endl;}int main(){ Time t(10,13,56); Date d(12,25,2004); t.display(d); return 0;}

<img src="http://img.blog.csdn.net/20150420225311147" alt="" />

12. #include <iostream>using namespace std;template<class numtype>class Compare{ public: Compare(numtype a,numtype b); numtype max(); numtype min(); private: numtype x,y;};template<class numtype>Compare<numtype>::Compare(numtype a,numtype b){ x=a; y=b;}template<class numtype>numtype Compare<numtype>::max(){return (x>y)?x:y;}template<class numtype>numtype Compare<numtype>::min(){    return (x<y)?x:y;}int main(){Compare<int> cmp1(3,7);cout<<cmp1.max()<<"is the Maximum of two integer numbers."<<endl;cout<<cmp1.min()<<"is the Minimum of two integer numbers."<<endl;Compare<float> cmp2(45.78,93.6);cout<<cmp2.max()<<"is the Maximum of two integer numbers."<<endl;cout<<cmp2.min()<<"is the Minimum of two integer numbers."<<endl;Compare<char> cmp3('a','A');cout<<cmp3.max()<<"is the Maximum of two characters."<<endl;cout<<cmp3.min()<<"is the Minimum of two characters."<<endl;}

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