谭浩强C++（第三版）(3)-9-11章

9-3

#include<iostream>
using namespace std;
class Date{
public:
    //有默认参数的构造函数不能重载，会引起歧义
    Date(int=1,int=1,int=2005);
    void display();
private:
    int month;
    int year;
    int day;
};
Date::Date(int m,int d,int y):month(m),day(d),year(y){
}
void Date::display() {
    cout<<month<<"/"<<day<<"/"<<year<<endl;
}
int main(){
    Date d1(10,13,2005);
    Date d2(12,30);
    Date d3(10);
    Date d4;
    d1.display();
    d2.display();
    d3.display();
    d4.display();
    return 0;
}

9-4

#include<iostream>
using namespace std;
class Student{
public:
    Student(int ,float );
    void display();
private:
    int num;
    float score;
};
Student::Student(int n,float s):num(n),score(s){
}
void Student::display() {
    cout<<num<<" "<<score<<endl;
}
int main(){
    Student stu[5]={Student(101,78.5),Student(102,85.5),Student(103,98.5),Student(104,100.0),Student(105,95.5)},*p;
    p=stu;int i;
    for(i=0;i<5;i+=2)
        (p+i)->display();
    return 0;
}

9-5

#include<iostream>
using namespace std;
class Student{
public:
    Student(int ,float );
    int max_value(Student *s);
    void display();
    int num;
    float score;
};
Student::Student(int n,float s):num(n),score(s){
}
int Student::max_value(Student *s){
    float max_m=s[0].score;
    int m=0;
    for(int i=0;i<5;i++)
    if(s[i].score>max_m){
        max_m=s[i].score;m=i;
    }
   return m;
}
void Student::display() {
    cout<<num<<" "<<score<<endl;
}
int main(){
    Student stu[5]={Student(101,78.5),Student(102,85.5),Student(103,98.5),Student(104,100.0),Student(105,95.5)},*p;
    int m;
    m=stu[5].max_value(stu);
    cout<<stu[m].score<<" has best score."<<endl;
    return 0;
}

9-7-1

#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;
    }
    //常对象只能调用常成员函数
    void display() const{
    cout<<num<<" "<<score<<endl;
}
private:
    int num;
    float score;
};
int main(){
    const Student stud(101,78.5);
    stud.display();
    return 0;
}

9-7-2

#include<iostream>
using namespace std;
class Student{
public:
    Student(int n,float s):num(n),score(s){
    }
    void change(int n,float s) const{
    num=n;score=s;
    }
    void display() const{
    cout<<num<<" "<<score<<endl;
}
private:
    mutable int  num;
    mutable int  score;
};

int main(){
    //想修改常函数，改为mutable,成员函数改为const
    const Student stud(101,78.5);
    stud.display();
    stud.change(101,80.5);
    stud.display();
    return 0;
}

9-7-3

//通过指针修改
#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;
}

9-7-4

#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() const{
    cout<<num<<" "<<score<<endl;
}
private:
    int num;
    float score;
};
int main(){
    Student stud(101,78.5);
    //指向常对象的指针变量，不通过指针修改即可,成员函数const
    const Student *p=&stud;
    p->display();
    stud.change(101,80.5);
     p->display();
    return 0;
}

9-7-5

#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);
    //指向对象的常指针，不改变指针指向的对象即可
    Student *const p=&stud;
    p->display();
    p->change(101,80.5);
     p->display();
    return 0;
}

9-8

#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;
};
void fun(Student &stu);
int main(){
    Student stud(101,78.5);
    fun(stud);
    return 0;
}
void fun(Student &stud){
    stud.display();
    stud.change(101,80.5);
     stud.display();
}

9-9

#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;

};
float Product::discount=0.05;
float Product::sum=0;
int Product::n=0;
int main(){
    Product pro[3]={
        Product(101,5,23.5),
        Product(102,12,24.56),
        Product(103,100,21.5)
    };
    for(int i=0;i<3;i++)
        pro[i].total();
    Product::display();
    return 0;
}
void Product::total(){
    if(quantity>=10)
        sum+=quantity*price*0.98*(1-discount);
    else
        sum+=quantity*price*(1-discount);
    n+=quantity;
}
float Product::average(){
    return sum/n;
}
void Product::display(){
    cout<<"Sum:"<<sum<<" "<<"average:"<<average()<<endl;
}

9-10

#include<iostream>
using namespace std;
class Date;
class Time{
public:
    Time(int,int,int);
    friend void display(Date &d,Time &t);
private:
    int hour;int minute;int sec;
};
class Date{
public:
    Date(int,int,int);
    friend void display(Date &d,Time &t);
private:
    int month;int day;int year;
};
Time::Time(int h,int m,int s){
    hour=h;minute=m;sec=s;
}
Date::Date(int m,int d,int y){
    month=m;day=d;year=y;
}
int main(){
    Time t1(10,13,56);
    Date d1(12 ,25 ,2004);
    display(d1,t1);
    return 0;
}
void display(Date &d,Time &t){
    cout<<d.month<<"/"<<d.day<<"/"<<d.year<<endl;
    cout<<t.hour<<":"<<t.minute<<":"<<t.sec<<endl;
}

9-11

#include<iostream>
using namespace std;
class Date;
class Time{
public:
    Time(int,int,int);
    void display( Date &);
private:
    int hour;int minute;int sec;
};
class Date{
public:
    Date(int,int,int);
    friend Time;
private:
    int month;int day;int year;
};

Time::Time(int h,int m,int s){
    hour=h;minute=m;sec=s;
}
void Time::display( Date &d){
    cout<<d.month<<"/"<<d.day<<"/"<<d.year<<endl;
    cout<<hour<<":"<<minute<<":"<<sec<<endl;
}

Date::Date(int m,int d,int y){
    month=m;day=d;year=y;
}

int main(){
    Time t1(10,13,56);
    Date d1(12 ,25 ,2004);
    t1.display(d1);
    return 0;
}

9-12

#include<iostream>
using namespace std;
template <class numtype>
class Compare{
public:
    Compare(numtype a,numtype b);
    numtype max_value();
    numtype min_value();
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_value(){
        return (x>y)?x:y;
}
template <class numtype>
numtype Compare<numtype>::min_value(){
        return (x<y)?x:y;
}

int main(){
    Compare<int> cmp1(3,7);
     cout<<cmp1.max_value()<<" is the Maximum of two integer numbers."<<endl;
     cout<<cmp1.min_value()<<" is the Minimum of two integer numbers."<<endl<<endl;
     Compare<float> cmp2(45.78,93.6);
     cout<<cmp2.max_value()<<" is the Maximum of two float numbers."<<endl;
     cout<<cmp2.min_value()<<" is the Minimum of two float numbers."<<endl<<endl;
     Compare<char> cmp3('a','A');
     cout<<cmp3.max_value()<<" is the Maximum of two characters."<<endl;
     cout<<cmp3.min_value()<<" is the Minimum of two characters."<<endl;
     return 0;
}

10-1

#include<iostream>
using namespace std;
class Complex{
public:
    Complex(){real=0;imag=0;}
    Complex(double r,double i){real=r;imag=i;}
    double get_real(){return real;}
    double get_imag(){return imag;}
    void display();
private:
    double real;
    double imag;
};
Complex operator + (Complex &c1,Complex &c2);
void Complex::display(){
    cout<<"("<<real;
    if(imag>=0)
        cout<<"+";
    cout<<imag<<"i)"<<endl;
}
int main(){
    Complex c1(4,3),c2(5,-10),c3;
    c3=c1+c2;
    cout<<"c1=";
    c1.display();
    cout<<"c2=";
    c2.display();
    cout<<"c3=";
    c3.display();
    return 0;
}
Complex operator + (Complex &c1,Complex &c2){
    return Complex(c1.get_real()+c2.get_real(),c1.get_imag()+c2.get_imag());
}

10-2

#include<iostream>
using namespace std;
class Complex{
public:
    Complex(){real=0;imag=0;}
    Complex(double r,double i){real=r;imag=i;}
    Complex operator+(Complex &c2);
    Complex operator-(Complex &c2);
    Complex operator*(Complex &c2);
    Complex operator/(Complex &c2);
    void display();
private:
    double real;
    double imag;
};
Complex Complex::operator+(Complex &c2){
    return Complex(real+c2.real,imag+c2.imag);
}
Complex Complex::operator-(Complex &c2){
    return Complex(real-c2.real,imag-c2.imag);
}
Complex Complex::operator*(Complex &c2){
    return Complex(real*c2.real-imag*c2.imag,real*c2.imag-imag*c2.real);
}
Complex Complex::operator/(Complex &c2){
    double a=c2.real*c2.real-c2.imag*c2.imag;
    real=real*c2.real+imag*c2.imag;
    imag=imag*c2.real-real*c2.imag;
    return Complex(real/a,imag/a);
}
void Complex::display(){
    cout<<real;
    if(imag>=0)
        cout<<"+";
    cout<<imag<<"i"<<endl;
}
int main(){
    Complex c1(2,1),c2(4,2),c3;
    cout<<"c1=";c1.display();
    cout<<"c2=";c2.display();
    cout<<"c3=";c3=c1+c2;c3.display();
    cout<<"c3=";c3=c1-c2;c3.display();
    cout<<"c3=";c3=c1*c2;c3.display();
    cout<<"c3=";c3=c1/c2;c3.display();
    return 0;
}

10-3

 #include<iostream>
using namespace std;
class Complex{
public:
    Complex(){real=0;imag=0;}
    Complex(double r,double i){real=r;imag=i;}
    Complex(double r) {real=r;imag=0;}
    friend Complex operator+(Complex c1, Complex c2);
    void display();
private:
    double real;
    double imag;
};
Complex operator+(Complex c1, Complex c2){
    return Complex(c1.real+c2.real,c1.imag+c2.imag);
}
void Complex::display(){
    cout<<real;
    if(imag>=0)
        cout<<"+";
    cout<<imag<<"i"<<endl;
}
int main(){
    Complex c1(2,1),c2(4,2),c3;
    int i=5;
    cout<<"c1=";c1.display();
    cout<<"c2=";c2.display();
    cout<<"c3=";c3=c1+c2;c3.display();
    cout<<"c3=";c3=c1+i;c3.display();
    cout<<"c3=";c3=i+c1;c3.display();
    return 0;
}

10-4

#include<iostream>
#include<iomanip>
using namespace std;
class Matrix{
public:
    Matrix();
    Matrix operator+(Matrix &m);
    void input();
    void display();
private:
    int a[2][3];
}ma;
Matrix::Matrix(){
    int i,j;
    for(i=0;i<2;i++)
        for(j=0;j<3;j++)
            a[i][j]=0;
}
void Matrix::input(){
    int i,j;
    for(i=0;i<2;i++)
        for(j=0;j<3;j++)
            cin>>a[i][j];
}
void Matrix::display(){
    int i,j;
    for(i=0;i<2;i++){
        for(j=0;j<3;j++)
            cout<<setw(5)<<a[i][j]<<"  ";
        cout<<endl;
    }
}
Matrix Matrix::operator+(Matrix &m){
    int i,j;
    for(i=0;i<2;i++)
        for(j=0;j<3;j++)
            ma.a[i][j]=a[i][j]+m.a[i][j];
    return ma;
}
int main(){
    Matrix m1,m2,m3;
    cout<<"Please enter m1:";
    m1.input();
    cout<<endl;
    cout<<"Please enter m2:";
    m2.input();
    cout<<endl;
     cout<<"t1:"<<endl;
    m1.display();
    cout<<"t2:"<<endl;
    m2.display();
    cout<<"t3:"<<endl;
    m3=m1+m2;
    m3.display();
    return 0;
}

10-5

#include<iostream>
#include<iomanip>
using namespace std;
class Matrix{
public:
    Matrix();
    Matrix operator+(Matrix &m);
    friend ostream& operator <<(ostream &output,Matrix &m);
   friend istream& operator >>(istream &input,Matrix &m);
private:
    int a[2][3];
}ma;
Matrix::Matrix(){
    int i,j;
    for(i=0;i<2;i++)
        for(j=0;j<3;j++)
            a[i][j]=0;
}
Matrix Matrix::operator+(Matrix &m){
    int i,j;
    for(i=0;i<2;i++)
        for(j=0;j<3;j++)
            ma.a[i][j]=a[i][j]+m.a[i][j];
    return ma;
}
ostream& operator <<(ostream &output,Matrix &m){
    int i,j;
    output<<"The matrix is : "<<endl;
    for(i=0;i<2;i++){
        for(j=0;j<3;j++)
            output<<setw(5)<<m.a[i][j]<<"  ";
        output<<endl;
    }
    return output;
}
istream& operator >>(istream &input,Matrix &m){
    int i,j;
    cout<<"Please enter the matrix : "<<endl;
    for(i=0;i<2;i++){
        for(j=0;j<3;j++)
            input>>m.a[i][j];
    }
    return input;
}
int main(){
    Matrix m1,m2,m3;
    cin>>m1;
    cin>>m2;
    cout<<m1;
    cout<<m2;
    m3=m1+m2;
    cout<<m3;
    return 0;
}

10-6

#include<iostream>
#include<iomanip>
using namespace std;
class Complex{
public:
    Complex(){real=0;imag=0;}
    Complex(double r){real=r;imag=0;}
    Complex(double r,double i){real=r;imag=i;}
    operator double(){return real;}
    void display();
private:
    double real;
    double imag;
};
void Complex::display(){
    cout<<real;
    if(imag>=0)
        cout<<"+";
    cout<<imag<<"i"<<endl;
}
int main(){
    Complex c1(3,-4);
    double d1=2.5,d2;
    d2=d1+c1;
    cout<<"d2="<<d2<<endl;
    cout<<"c2=";
    Complex(d2).display();
    return 0;
}

10-7

#include<iostream>
using namespace std;
class Student{
public:
    Student(int nu ,string na,char se,float sc){num=nu;name=na;sex=se;score=sc;}
    int get_num(){return num;}
    string get_name(){return name;}
    char get_sex(){return sex;}
    float get_score(){return score;}
    void display(){
        cout<<"num:"<<num<<"   name:"<<name<<"   sex:"<<sex<<"   score:"<<score<<endl;
    }
private:
    int num;
    string name;
    char sex;
    float score;
};
class Teacher{
public:
    Teacher(){}
    Teacher(Student &stu){
        num=stu.get_num();name=stu.get_name();sex=stu.get_sex();pay=2000;
    }
    Teacher(int nu ,string na,char se,float p){num=nu;name=na;sex=se;pay=p;}
    void display(){
        cout<<"num:"<<num<<"   name:"<<name<<"   sex:"<<sex<<"   pay:"<<pay<<endl;
    }
private:
    int num;
    string name;
    char sex;
    float pay;//工资
};
int main(){
    Teacher t1(1001,"Tang",'f',2500),t2;
    Student s1(1002,"Zhou",'m',90);
    cout<<"Teacher 1 : ";
    t1.display();
    cout<<endl<<"Student 2 : ";
    s1.display();
    t2=Teacher(s1);
    cout<<endl<<"Teacher 2 : ";
    t2.display();
    return 0;
}

11-1

#include<iostream>
using namespace std;
class Student{
public:
    void get_value(){
        cin>>num>>name>>sex;
       }
    void display(){
        cout<<"num: "<<num<<endl;
        cout<<"name: "<<name<<endl;
        cout<<"sex: "<<sex<<endl;
    }
private:
    int num;
    string name;
    char sex;
};
class Student1:public Student{
public:
    void get_value_1(){
        cin>>age>>addr;
    }
    void display_1(){
        cout<<"age: "<<age<<endl;
        cout<<"address: "<<addr<<endl;
    }
private:
    int age;
    string addr;
};
int main(){
    Student1 stu;
    stu.get_value();
    stu.get_value_1();
    stu.display();
    stu.display_1();
    return 0;
}

11-2

#include<iostream>
using namespace std;
class Student{
public:
    void get_value(){
        cin>>num>>name>>sex;
       }
    void display(){
        cout<<"num: "<<num<<endl;
        cout<<"name: "<<name<<endl;
        cout<<"sex: "<<sex<<endl;
    }
private:
    int num;
    string name;
    char sex;
};
class Student1:private Student{
public:
    void get_value_1(){
        get_value();
        cin>>age>>addr;
    }
    void display_1(){
        display();
        cout<<"age: "<<age<<endl;
        cout<<"address: "<<addr<<endl;
    }
private:
    int age;
    string addr;
};
int main(){
    Student1 stu;
    stu.get_value_1();
    stu.display_1();
    return 0;
}

11-3

#include<iostream>
using namespace std;
class Student{
public:
protected:
    int num;
    string name;
    char sex;
};
class Student1:protected Student{
public:
    void get_value_1(){
        cin>>num>>name>>sex;
        cin>>age>>addr;
    }
    void display_1(){
        cout<<"num: "<<num<<endl;
        cout<<"name: "<<name<<endl;
        cout<<"sex: "<<sex<<endl;
        cout<<"age: "<<age<<endl;
        cout<<"address: "<<addr<<endl;
    }
private:
    int age;
    string addr;
};
int main(){
    Student1 stu;
    stu.get_value_1();
    stu.display_1();
    return 0;
}

11-4

#include<iostream>
using namespace std;
class Student{
public:
protected:
    int num;
    string name;
    char sex;
};
class Student1:public Student{
public:
    void get_value_1(){
        cin>>num>>name>>sex;
        cin>>age>>addr;
    }
    void display_1(){
        cout<<"num: "<<num<<endl;
        cout<<"name: "<<name<<endl;
        cout<<"sex: "<<sex<<endl;
        cout<<"age: "<<age<<endl;
        cout<<"address: "<<addr<<endl;
    }
private:
    int age;
    string addr;
};
int main(){
    Student1 stu;
    stu.get_value_1();
    stu.display_1();
    return 0;
}

11-9

#include<iostream>
#include<string>
using namespace std;
class Teacher{
public:
    Teacher(){}
    Teacher(string nam,int a,char s,string ad,string t,string tit);
    void display();
protected:
    int age;string name;char sex; string addr;string tell;string title;//职称
};
class Cadre{
public:
    Cadre(){}
    Cadre(string nam,int a,char s,string ad,string t,string p);
protected:
     int age;string name; char sex;string addr; string tell;string post;//职务
};
class Teacher_Cadre:public Teacher,public Cadre {
public:
    Teacher_Cadre(){}
    Teacher_Cadre(string nam,int a,char s,string ad,string t,string tit,string p,float w):
        Teacher(nam,a,s,ad,t,tit),
        Cadre(nam,a,s,ad,t,p),
        wages(w){}
    void show();
private:
    float wages;
};
Teacher::Teacher(string nam,int a,char s,string ad,string t,string tit){
        age=a;name=nam;sex=s;addr=ad;tell=t;title=tit;
    }
void Teacher::display(){
        cout<<"name: "<<name<<endl;
         cout<<"age: "<<age<<endl;
        cout<<"sex: "<<sex<<endl;
        cout<<"address: "<<addr<<endl;
        cout<<"tell: "<<tell<<endl;
        cout<<"title: "<<title<<endl;
    }
Cadre::Cadre(string nam,int a,char s,string ad,string t,string p){
        age=a;name=nam;sex=s;addr=ad;tell=t;post=p;
    }
void Teacher_Cadre::show(){
        Teacher::display();
        cout<<"post: "<<Cadre::post<<endl;
        cout<<"wage: "<<wages<<endl;
    }
int main(){
   Teacher_Cadre tc("Tang",21,'f',"Shanghai","1888888","Professor","minister",3000);
   tc.show();
    return 0;
}

11-10

#include<iostream>
#include<string>
using namespace std;
class Teacher{
public:
    Teacher(string n,int a,char s):name(n),age(a),sex(s){}
    void display(){
       cout<<"Name:"<<name<<endl;cout<<"Age:"<<age<<endl;cout<<"Sex:"<<sex<<endl;
    }
private:
    int age;string name;char sex;
};
class BirthDate{
public:
    BirthDate(int y,int m,int d):year(y),month(m),day(d){}
    void change(int y,int m,int d){
        year=y;month=m;day=d;
    }
    void display_1(){
        cout<<"Birthday:"<<year<<"/"<<month<<"/"<<day<<endl;
    }
private:
     int year;int month;int day;
};
class Professor:public Teacher {
public:
    Professor(string n,int a,char s,int y,int m,int d): Teacher( n,a,s),birthday(y,m,d){}
    void change(int y,int m,int d){birthday.change(y,m,d);}
    void show(){
         Teacher::display();
         birthday.display_1();
    }
private:
   BirthDate birthday;
};

int main(){
   Professor p("Zhang",21,'f',1999,2,16);
   p.show();
   p.change(1999,7,14);
   p.show();
    return 0;
}