实验一 类与对象

实验三

#include <iostream>

#include <cmath>

using namespace std;

class Complex{

private:

double real;

double imag;

public:

Complex();

Complex(double a,double b):real(a),imag(b){}

Complex(Complex &n);

double get_real(Complex c)

{

return real;

}

double get_imag(Complex c)

{

return imag;

}

void show(Complex &c);

void add(Complex &c);

friend Complex add(Complex &c1,Complex &c2);

friend bool is_equal(Complex &c1,Complex &c2);

friend double abs(Complex &c1);

};

void Complex::show(Complex &c)

{

if(c.real==0)

{

if(c.imag!=0)

cout<<c.imag<<"i";

else

cout<<"0";

}

else

{

if(c.imag==0)

cout<<c.real;

if(c.imag>0)

cout<<c.real<<"+"<<c.imag<<"i";

if(c.imag<0)

cout<<c.real<<c.imag<<"i";

}

}

void Complex::add(Complex &c)

{

real+=c.real;

imag+=c.imag;

}

Complex add(Complex &c1,Complex&c2)

{

Complex c3;

c3.real=c2.real+c1.real;

c3.imag=c2.imag+c1.imag;

return c3;

}

bool is_equal(Complex &c1,Complex &c2)

{

if(c1.real==c2.real&&c1.imag==c2.imag)

return 1;

else

return 0;

}

double abs(Complex &c)

{

    return sqrt(c.real*c.real+c.imag*c.imag);

}

task.3 cpp

#include "Complex.hpp"

#include <iostream>

 

int main()

{

    using namespace std;

 

    Complex c1(3, -4);

    const Complex c2(4.5);

    Complex c3(c1);

 

    cout << "c1 = ";

    c1.show();

    cout << endl;

 

    cout << "c2 = ";

    c2.show();

    cout << endl;

    cout << "c2.imag = " << c2.get_imag() << endl;

 

    cout << "c3 = ";

    c3.show();

    cout << endl;

 

    cout << "abs(c1) = ";

    cout << abs(c1) << endl;

 

    cout << boolalpha;

    cout << "c1 == c3 : " << is_equal(c1, c3) << endl;

    cout << "c1 == c2 : " << is_equal(c1, c2) << endl;

 

    Complex c4;

    c4 = add(c1, c2);

    cout << "c4 = c1 + c2 = ";

    c4.show();

    cout << endl;

 

    c1.add(c2);

    cout << "c1 += c2, " << "c1 = ";

    c1.show();

    cout << endl;

}

 

 

 

实验四

#include<iostream>

#include<string>

using namespace std;

class User 

{

    private:

        string name,password,email;

        static int n;

    public:

        User(string x) {name=x; password="111111"; email='\0'; n++;}

        User(string x,string y,string z) {name=x; password=y; email=z; n++;}

        void set_email(); void change_passwd();

        void print_info();

        static void print_n();

};

int User::n=0;

void User::print_n() {

    cout<<"there are "<<n<<"users";

}

void User::set_email() {

    cout<<"Enter email address:";

    string x;

    cin>>x;

    cout<<"email is set successfully..."<<endl;

}

void User::change_passwd()

{

    cout<<"Enter old password: ";

    string A,B;

    for(int i=1;i<=3;i++)

    { 

         cin>>A;

         if(A==password)

         {

             cout<<"Enter new password: ";

             cin>>B;

             cout<<"new password is set successfully..."<<endl;

         }

         else if(i<=2&&A!=password)

         {

             cout<<"password input error. Please re-enter again: ";

         }

         else

             cout<<"Password input error.Please try after a while."<<endl;

     }

}

void User::print_info()

{

    cout<<"name: "<<name<<endl;

    cout<<"passwd: ******"<<endl;

    cout<<"email: " <<email<<endl;

}

//#endif

#include "User.h"

#include <iostream>

int main()

{

    using namespace std;

    cout << "testing 1......" << endl;

    User user1("Polaris", "010314", "sct@hotmail.com");

    user1.print_info();

    cout << endl

         << "testing 2......" << endl

         << endl;

    User user2("Leonard");

    user2.change_passwd();

    user2.set_email();

    user2.print_info();

    User::print_n();

}


task4.cpp

#include "User.hpp"

#include <iostream>

int main()

{

    using namespace std;

    cout << "testing 1......" << endl;

    User user1("Jonny", "92197", "xyz@hotmail.com");

    user1.print_info();

    cout << endl

        << "testing 2......" << endl

        << endl;

    User user2("Leonard");

    user2.change_passwd();

    user2.set_email();

    user2.print_info();

    User::print_n();

}