#include <iostream>
#include <complex>
int main(){
using namespace std;
complex<double> c1{3, 4}, c2{4.5};
const complex<double> c3{c2};
cout << "c1 = " << c1 << endl;
cout << "c2 = " << c2 << endl;
cout << "c3 = " << c3 << endl;
cout << "c3.real = " << c3.real() << endl;
cout << "c3.imag = " << c3.imag() << endl;
cout << "c1 + c2 = " << c1 + c2 << endl;
cout << "c1 - c2 = " << c1 - c2 << endl;
cout << "abs(c1) = " << abs(c1) << endl;
cout << boolalpha;
cout << "c1 == c2 : " << (c1 == c2) << endl;
cout << "c3 == c2 : " << (c3 == c2) << endl;
complex<double> c4 = 2;
cout << "c4 = " << c4 << endl;
c4 += c1;
cout << "c4 = " << c4 << endl;
}
#include <iostream>
#include <array>
#include <string>
template<typename T>
void output1(const T &obj) {
for(auto i: obj)
std::cout << i << ", ";
std::cout << "\b\b \n";
}
template<typename T>
void output2(const T &obj) {
for(auto p = obj.cbegin(); p != obj.cend(); ++p)
std::cout << *p << ", ";
std::cout << "\b\b \n";
}
int main() {
using namespace std;
array<int, 5> x1;
cout << "x1.size() = " << x1.size() << endl;
x1.fill(42);
x1.at(0) = 999;
x1.at(4) = -999;
x1[1] = 777;
cout << "x1: ";
output1(x1);
cout << "x1: ";
output2(x1);
array<double, 10> x2{1.5, 2.2};
cout << "x2.size() = " << x2.size() << endl;
cout << "x2: ";
output1(x2);
array<int, 5> x3(x1);
cout << boolalpha << (x1 == x3) << endl;
x3.fill(22);
cout << "x3: ";
output1(x3);
swap(x1, x3);
cout << "x1: ";
output1(x1);
cout << "x3: ";
output1(x3);
}
#include "Employee.hpp"
#include <iostream>
void test() {
using std::cout;
using std::endl;
cout << Employee::doc << endl << endl;
Employee employee1;
employee1.set_info("Sam", 30000, 2015, 1, 6);
employee1.update_hire_date(2017, 6, 30);
employee1.update_salary(35000);
employee1.display_info();
cout << endl << endl;
Employee employee2{ "Tony", 20000, 2020, 3, 16 };
employee2.raise_salary(15);
employee2.display_info();
cout << endl << endl;
Employee::display_count();
}
int main() {
test();
}
#pragma once
#pragma once
#include <iostream>
#include <string>
#include <iomanip>
using std::string;
using std::cout;
using std::endl;
using std::setfill;
using std::setw;
using std::left;
using std::right;
using std::to_string;
struct Date {
int year;
int month;
int day;
};
class Employee
{
public:
Employee();
Employee(string name0, double salary0, int y, int m, int d = 1);
void set_info(string name0, double salary0, int y, int m, int d = 1);
string get_name() const;
double get_salary() const;
void display_info() const;
void update_salary(double s);
void update_hire_date(int y, int m, int d);
void raise_salary(double by_percent);
public:
static void display_count();
private:
string id;
string name;
double salary;
Date hire_date;
public:
static const string doc;
private:
static int count;
};
const string Employee::doc{ "a simple Employee class" };
int Employee::count = 0;
Employee::Employee() : id{ to_string(count + 1) } {
++count;
}
Employee::Employee(string name0, double salary0, int y, int m, int d) :
id{ to_string(count + 1) }, name{ name0 }, salary{ salary0 }, hire_date{ y, m, d } {
++count;
}
void Employee::set_info(string name0, double salary0, int y, int m, int d) {
name = name0;
salary = salary0;
hire_date.year = y;
hire_date.month = m;
hire_date.day = d;
}
string Employee::get_name() const {
return name;
}
double Employee::get_salary() const {
return salary;
}
void Employee::display_info() const {
cout << left << setw(15) << "id: " << id << endl;
cout << setw(15) << "name: " << name << endl;
cout << setw(15) << "salary: " << salary << endl;
cout << setw(15) << "hire_date: " << hire_date.year << "-";
cout << std::right << setfill('0') << setw(2) << hire_date.month << "-" << setw(2) << hire_date.day;
cout << setfill(' ');
}
void Employee::update_salary(double s) {
salary = s;
}
void Employee::update_hire_date(int y, int m, int d) {
hire_date.year = y;
hire_date.month = m;
hire_date.day = d;
}
void Employee::raise_salary(double by_percent) {
double raise = salary * by_percent / 100;
salary += raise;
}
void Employee::display_count() {
cout << "there are " << count << " employees\n";
}
#include "Complex.h"
#include <iostream>
void test() {
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;
}
int main() {
test();
}
#pragma once
#include<iostream>
#include<cmath>
using namespace std;
class Complex {
public:
Complex(float x = 0, float y = 0) {
real = x;
imag = y;
}
Complex(Complex& c1);
int get_real()const { return real; }
int get_imag()const { return imag; }
friend Complex add(Complex& c1, const Complex& c2);
friend bool is_equal(const Complex& c1, const Complex& c2);
friend float abs(Complex& c1);
void show()const;
void add( const Complex& c1);
private:
float real, imag;
};
Complex::Complex(Complex& c1) {
real = c1.real;
imag = c1.imag;
}
void Complex::show()const {
if (imag == 0)
cout << real;
else if (imag < 0)
cout << real << "-" << abs(imag) << "i";
else
cout << real << "+" << imag << "i";
}
void Complex::add(const Complex& c1) {
real += c1.real;
imag += c1.imag;
}
Complex add(Complex& c1,const Complex& c2) {
Complex c3;
c3.real = c1.real + c2.real;
c3.imag = c1.imag + c2.imag;
return c3;
}
bool is_equal(const Complex& c1,const Complex& c2) {
if (c1.real == c2.real && c1.imag == c2.imag)
return true;
else
return false;
}
float abs(Complex& c1) {
return sqrt(c1.real * c1.real + c1.imag * c1.imag);
}
#include "User.hpp"
#include <iostream>
void test() {
using std::cout;
using std::endl;
cout << "testing 1......\n";
User user1("Jonny", "92197", "[email protected]");
user1.print_info();
cout << endl
<< "testing 2......\n\n";
User user2("Leonard");
user2.change_passwd();
user2.set_email();
user2.print_info();
cout << endl;
User::print_n();
}
int main() {
test();
}
#pragma once
#include<iostream>
#include<string>
#include<iomanip>
using namespace std;
class User {
public:
User(string name0, string passwd0 = "111111", string email0 = "") :name{ name0 }, password{ passwd0 }, email{ email0 } { count ++; }
~User() = default;
void set_email();
void change_passwd();
void print_info();
static void print_n();
private:
string name;
string password;
string email;
static int count;
};
int User::count = 0;
void User::set_email() {
cout << "Enter email address:";
cin >> email;
cout << "email is set successfully..." << endl;
}
void User::change_passwd() {
for (int i = 1; i <= 3; i++)
{
string password1;
if (i == 1)
cout << "Enter old password:";
cin >> password1;
if (password1 == password) {
cout << "Enter new password:";
cin >> password;
cout << "new password is set successfully..." << endl;
break;
}
else
{
if (i == 1 || i == 2)
cout << "password input error.Please re-enter again:";
if(i==3)
cout << "password input error.Please try after a while:" << endl;
}
}
}
void User::print_info() {
cout <<left<<setw(10) << "name:" << name << endl;
cout << setw(10) << "password:" ;
for (int j = 0; j <password.length(); j++)
cout << "*";
cout << endl;
cout <<setw(10) << "email:" << email << endl;
}
void User::print_n() {
cout << "there are" << count << "users.";
}
标签：const,string,int,void,Complex,实验,cout From： https://www.cnblogs.com/hjr123/p/16785687.html