【C++】继承和运算符重载练习题

运算符重载

#include <iostream>
using namespace std;
#include <string>
class Money
{
public:
    Money(int y = 0, int j = 0, int f = 0);
    Money operator+(Money &);
    void Display(string);

private:
    int yuan, jiao, fen;
    void Optimize();
};
void Money::Optimize()
{
    if (fen >= 10)
    {
        jiao++;
        fen -= 10;
    }
    if (jiao >= 10)
    {
        yuan++;
        jiao -= 10;
    }
}
Money::Money(int y, int j, int f)
{
    yuan = y;
    jiao = j;
    fen = f;
    Optimize();
}
Money Money::operator+(Money &c2)
{
    return Money(yuan + c2.yuan, jiao + c2.jiao, fen + c2.fen);
}
void Money::Display(string str)
{
    cout << str << " = " << yuan << "." << jiao << fen << "￥" << endl;
}
int main()
{
    Money cost1(300, 5, 6), cost2(105, 7, 6), total1, total2;
    // cost1+cost2解释为：cost1.operator+(cost2)
    total1 = cost1 + cost2;
    total2 = cost1.operator+(cost2);
    total1.Display("total1 = cost1 + cost2");
    total2.Display("total2 = cost1 + cost2");
    // total1 = cost1 + cost2 = 406.32￥  total2 = cost1 + cost2 = 406.32￥
    return 0;
}

#include <math.h>
#include <iostream>
using namespace std;
class Rational // 声明有理数类
{
public:
  Rational(int x = 0, int y = 1); // 构造函数
  void Print();
  Rational operator+(Rational a); // 重载运算符"+"
  Rational operator-(Rational a); // 重载运算符"-"
private:
  int num, den;
  void Optimi();
};                      // 优化有理数函数
// 声明构造函数
Rational::Rational(int x, int y) : num(x), den(y)
{
  Optimi();
}
void Rational::Optimi() // 定义有理数优化函数
{
  // 最大公约数
  int gcd;
  if (num == 0) // 若分子为0，则置分母为1后返回
  {
    den = 1;
    return;
  }
  gcd = (abs(num) > abs(den) ? abs(num) : abs(den));
  if (gcd == 0)
    return;                     // 若为0，则返回
  int i = gcd;
  for (; i > 1; i--) // 用循环找最大公约数
  {
    if ((num % i == 0) && (den % i == 0))
      break;
  }
  num /= i; // i为最大公约数,将分子、分母均整除它,重新赋值
  den /= i;
  // 若分子和分母均为负数，则结果为正，所以均改为正
  if (num < 0 && den < 0)
  {
    num = -num;
    den = -den;
  }
  else if (num < 0 || den < 0)
  { // 若分子和分母中只有一个为负数，则调整为分子取负，分母取正
    num = -abs(num);
    den = abs(den);
  }
}
void Rational::Print() // 输出有理数
{
  cout << num;
  // 当分子不为0且分母不为1时才显示"/分母“
  if (num != 0 && den != 1)
    cout << "/" << den << "\n";
  else
    cout << "\n";
}
Rational Rational::operator+(Rational a)
{ // “+”运算符重载函数，根据前面所列的算法写出表达式
  Rational r;
  r.den = a.den * den;
  r.num = a.num * den + a.den * num;
  r.Optimi();
  return r;
}
Rational Rational::operator-(Rational a)
{ // “-”运算符重载函数，根据前面所列的算法写出表达式
  Rational r;
  r.den = a.den * den;
  r.num = num * a.den - den * a.num;
  r.Optimi();
  return r;
}
int main()
{
  Rational r1(3, 14), r2(4, 14), r3, r4;
  r1.Print();
  r2.Print();
  r3 = r1 + r2; // 使用重载了的运算符“+”
  r3.Print();
  r4 = r1 - r2; // 使用重载了的运算符“-”
  r4.Print();
  return 0;
}

#include <math.h>
#include <iostream>
using namespace std;
class rational // 声明有理数类
{
public:
  // 重载函数作为友元函数
  rational(int x = 0, int y = 1);
  friend rational operator+(rational a, rational b);
  // 重载函数作为友元函数
  friend rational operator-(rational a, rational b);
  void print();

private:
  int num, den;
  void optimi();
};
rational::rational(int x, int y) : num(x), den(y)
{
  optimi();
}
void rational::optimi() // 定义有理数优化函数
{
  // 最大公约数
  int gcd;
  if (num == 0) // 若分子为0，则置分母为1后返回
  {
    den = 1;
    return;
  }
  gcd = (abs(num) > abs(den) ? abs(num) : abs(den));
  if (gcd == 0)
    return; // 若为0，则返回
  int i = gcd;
  for (; i > 1; i--) // 用循环找最大公约数
  {
    if ((num % i == 0) && (den % i == 0))
      break;
  }
  num /= i; // i为最大公约数,将分子、分母均整除它,重新赋值
  den /= i;
  // 若分子和分母均为负数，则结果为正，所以均改为正
  if (num < 0 && den < 0)
  {
    num = -num;
    den = -den;
  }
  else if (num < 0 || den < 0)
  { // 若分子和分母中只有一个为负数，则调整为分子取负，分母取正
    num = -abs(num);
    den = abs(den);
  }
}
// 定义作为友元函数的重载函数
rational operator+(rational a, rational b)
{
  rational r;
  r.den = a.den * b.den;
  r.num = a.num * b.den + a.den * b.num;
  r.optimi();
  return r;
}
// 定义作为友元函数的重载函数
rational operator-(rational a, rational b)
{
  rational r;
  r.den = a.den * b.den;
  r.num = a.num * b.den - a.den * b.num;
  r.optimi();
  return r;
}
void rational::print() // 输出有理数
{
  cout << num;
  // 当分子不为0且分母不为1时才显示"/分母“
  if (num != 0 && den != 1)
    cout << "/" << den << "\n";
  else
    cout << "\n";
}
int main()
{
  rational r1(3, 14), r2(4, 14), r3, r4;
  r1.print();
  r2.print();
  r3 = r1 + r2; // 使用重载了的运算符“+”
  r3.print();
  r4 = r1 - r2; // 使用重载了的运算符“-”
  r4.print();
  return 0;
}

#include <iostream>
using namespace std;
class Point
{
public:
  Point();
  Point(int vx, int vy); 
  // 前置自增重载为成员函数
  Point operator++();
 // 前置自减重载为友元函数
  friend Point &operator--(Point &p);
  void Display();

private:
  int x, y;
};
Point::Point()
{
  x = 0;
  y = 0;
}
Point::Point(int vx, int vy)
{
  x = vx;
  y = vy;
}
void Point::Display()
{
  cout << "(" << x << ", " << y << ")" << endl;
}
Point Point::operator++() // 前置自增
{
  if (x < 640)
    x++; // 不超过屏幕的横界
  if (y < 480)
    y++; // 不超过屏幕的竖界
  return *this;
}
Point &operator--(Point &p)
// 前置自减重载为友元函数
{
  if (p.x > 0)
    p.x--;
  if (p.y > 0)
    p.y--;
  return p;
}
int main()
{
  Point p1(10, 10), p2(150, 150);
  cout << "p1=";
  p1.Display();
  ++p1; // 测试前置自增
  cout << "++p1=";
  p1.Display();
  cout << "p2=";
  p2.Display();
  --p2; // 测试前置自减
  cout << "--p2=";
  p2.Display();
  return 0;
}

#include <iostream>
using namespace std;
class Point
{
public:
  Point();
  Point(int vx, int vy);
  Point &operator++();    // 重载前置自增为类的成员函数
  Point &operator++(int); // 重载后置自增为类的成员函数
  // 重载前置自减为类的友元函数
  friend Point& operator--(Point & p1);
  // 重载后置自减为类的友元函数
  friend Point& operator--(Point &p1, int);
  void display();

private:
  int x, y;
};
Point::Point()
{
  x = 0;
  y = 0;
}
Point::Point(int vx, int vy)
{
  x = vx;
  y = vy;
}
void Point::display()
{
  cout << " (" << x << "," << y << ") " << endl;
}
Point &Point::operator++() // 前置自增
{
  if (x < 640)
    x++; // 不超过屏幕的横界
  if (y < 480)
    y++; // 不超过屏幕的竖界 return *this;
  return *this;
}
Point &Point::operator++(int) // 后置自增
{                             // 先将当前对象通过复制构造函数临时保存起来
  Point temp(*this);
  if (x < 640)
    x++; // 不超过屏幕的横界
  if (y < 480)
    y++; // 不超过屏幕的竖界
  return temp;
}
Point &operator--(Point &p) // 前置自减
{
  if (p.x > 0)
    p.x--;
  if (p.y > 0)
    p.y--;
  return p;
}
Point& operator--(Point &p, int) // 后置自减
{                               // 先将当前对象通过复制构造函数临时保存起来
  Point temp(p);
  if (p.x > 0)
    p.x--;
  if (p.y > 0)
    p.y--;
  return temp;
}
int main()
{
  Point p1(10, 10), p2(150, 150), p3(20, 20),
      p4(160, 160), p5;
  cout << "p1=";
  p1.display();
  ++p1; // 测试前置自增
  cout << "++p1=";
  p1.display();
  cout << "p3=";
  p3.display();
  p5 = p3++; // 测试后置自增
  cout << " p3++=";
  p3.display();
  cout << "p5=p3++=";
  p5.display();
  cout << "p2=";
  p2.display();
  --p2; // 测试前置自减
  cout << "--p2=";
  p2.display();
  cout << "p4=";
  p4.display();
  p5 = p4--; // 测试后置自增
  cout << " p4--=";
  p4.display();
  cout << " p5= p4--=";
  p5.display();
  return 0;
}

#include <iostream>
using namespace std;
#include <cstring>
#include <cassert>
class String // 自定义字符串类
{
public:
  String();                // 默认构造函数
  String(const char *src); // 带参数的构造函数
  ~String();               // 析构函数
  const char *ToString() const { return str; }
  unsigned int Length() const { return len; }
  String &operator=(const String &right);
  // 赋值运算符重载函数
private:
  char *str;
  unsigned int len; // 存放字符串的长度
};
String::String() // 默认构造函数
{
  len = 0;
  str = new char[len + 1];
  str[0] = '\0';
}
String::String(const char *src) // 带参数的构造函数
{
  len = strlen(src);
  str = new char[len + 1];
  if (!str)
  {
    cerr << "Allocation Error!\n";
    exit(1);
  }
  strcpy(str, src);
}
String::~String() // 析构函数
{
  delete str;
  str = NULL;
}
String &String::operator=(const String &right)
// 赋值运算符重载函数
{
  if (&right != this)
  {
    int length = right.Length();
    if (len < length)
    {
      delete[] str;
      str = new char[length + 1];
      assert(str != 0);
    }
    int i;
    for (i = 0; right.str[i] != '\0'; i++)
      str[i] = right.str[i];
    str[i] = '\0';
    len = length;
  }
  return *this;
}
int main()
{
  String str1("Hi!"), str2("Hello!");
  cout << "str1: " << str1.ToString() << endl;
  cout << "str2: " << str2.ToString() << endl;
  str1 = str2;
  cout << "str1: " << str1.ToString() << endl;
  return 0;
}

#include <iostream>
using namespace std;
class Timer
{
public:
  Timer();
  Timer(int h, int m = 0);
  friend Timer operator+(Timer &t1, Timer &t2);
  friend Timer operator-(Timer &t1, Timer &t2);
  friend ostream &operator<<(ostream &out,
                             Timer &t);
  friend istream &operator>>(istream &in,
                             Timer &t);

private:
  int hours;
  int minutes;
};
Timer::Timer()
{
  hours = minutes = 0;
}
Timer::Timer(int h, int m)
{
  hours = h;
  minutes = m;
}
Timer operator+(Timer &t1, Timer &t2)
{
  Timer sum;
  sum.minutes = t1.minutes + t2.minutes;
  sum.hours = t1.hours + t2.hours + sum.minutes / 60;
  sum.minutes %= 60;
  return sum;
}
Timer operator-(Timer &t1, Timer &t2)
{
  Timer dif;
  int x1, x2;
  x1 = t2.hours * 60 + t2.minutes;
  x2 = t1.hours * 60 + t1.minutes;
  dif.minutes = (x2 - x1) % 60;
  dif.hours = (x2 - x1) / 60;
  return dif;
}
ostream &operator<<(ostream &out, Timer &t)
{
  out << t.hours << "hours," << t.minutes << "minutes";
  return out;
}
istream &operator>>(istream &in, Timer &t)
{
  cout << "Input hours and minutes:";
  in >> t.hours >> t.minutes;
  return in;
}
int main()
{
  Timer t1, t2, t3, t4;
  cin >> t1 >> t2;
  cout << "t1 = " << t1 << "\n";
  cout << "t2 = " << t2 << "\n";
  t3 = t1 + t2;
  cout << "t3 = t1 + t2 = " << t3 << "\n";
  t4 = t1 - t2;
  cout << "t4 = t1 - t2 = " << t4 << "\n";
  return 0;
}

#include <iostream>
using namespace std;
class Complex
{
  friend ostream &operator<<(ostream &out, Complex &c);
  friend istream &operator>>(istream &in, Complex &c);

public:
  Complex(double r = 1, double m = 1)
  {
    real = r;
    imag = m;
  }
  Complex operator+(Complex b)
  {
    Complex c;
    c.real = real + b.real;
    c.imag = imag + b.imag;
    return c;
  }

private:
  double real, imag;
};
ostream &operator<<(ostream &out, Complex &c)
{
  if (c.imag > 0)
    out << c.real << "+" << c.imag << "i" << endl;
  else
    out << c.real << "+(" << c.imag << ")i" << endl;
  return out;
}
istream &operator>>(istream &in, Complex &c)
{
  cout << "请输入复数的实部和虚部：" << endl;
  in >> c.real >> c.imag;
  return in;
}
int main()
{
  Complex a, b, c;
  cin >> a >> b;
  c = a + b;
  cout << "两个复数之和为：" << c << endl;
  return 0;
}

继承

3. 分别定义教师类Teacher和干部类Cadre,采用多重继承的方式由这两个类派生出新类Teacher_Cadre (教师兼干部类)。要求:(1)在两个基类中都包含姓名、年龄、性别、地址、电话数据成员。(2)在Teacher类中还包含数据成员职称title,在Cadre类中还包含数据成员职务post,在Teacher_Cadre类中还包含数据成员工资wage.(3)对两个基类中的姓名、年龄、性别、地址、电话数据成员用相同的名字，在访问这类数据成员时，指定作用域。(4)在类体中声明成员函数，在类外定义成员函数。(5)在派生类Teacher_Cadre的成员函数show中调用Teacher类中的display函数,输出姓名、年龄、性别、地址、电话,然后再用cout语句输出职务和工资。

#include <iostream>
#include <string>
using namespace std;

class Teacher
{
protected:
  string name;
  int age;
  string gender;
  string address;
  string phone;
  string title;

public:
  Teacher(string n, int a, string g, string ad, string p, string t);
  void display();
};
Teacher::Teacher(string n, int a, string g, string ad, string p, string t)
{
  name = n;
  age = a;
  gender = g;
  address = ad;
  phone = p;
  title = t;
}
void Teacher::display()
{
  cout << "Name: " << name << endl;
  cout << "Age: " << age << endl;
  cout << "Gender: " << gender << endl;
  cout << "Address: " << address << endl;
  cout << "Phone: " << phone << endl;
  cout << "Title: " << title << endl;
}
class Cadre
{
protected:
  string name;
  int age;
  string gender;
  string address;
  string phone;
  string post;

public:
  Cadre(string n, int a, string g, string ad, string p, string pst);
  void display();
};
Cadre::Cadre(string n, int a, string g, string ad, string p, string pst)
{
  name = n;
  age = a;
  gender = g;
  address = ad;
  phone = p;
  post = pst;
}
void Cadre::display()
{
  cout << "Name: " << name << endl;
  cout << "Age: " << age << endl;
  cout << "Gender: " << gender << endl;
  cout << "Address: " << address << endl;
  cout << "Phone: " << phone << endl;
  cout << "Post: " << post << endl;
}
class Teacher_Cadre : public Teacher, public Cadre
{
private:
  float wage;

public:
  Teacher_Cadre(string n, int a, string g, string ad, string p, string t, string pst, float w);
  void show();
};
Teacher_Cadre::Teacher_Cadre(string n, int a, string g, string ad, string p, string t, string pst, float w) : Teacher(n, a, g, ad, p, t), Cadre(n, a, g, ad, p, pst)
{
  wage = w;
}
void Teacher_Cadre::show()
{
  Teacher::display();
  cout << "Post: " << Cadre::post << endl;
  cout << "Wage: " << wage << endl;
  cout << endl;
}
int main()
{
  Teacher_Cadre tc("张三", 30, "男", "北京", "123456789", "教授", "部门主管", 5000.50);
  tc.show();
  return 0;
}

4. 编写一个程序实现小型公司的人员信息管理系统。该公司雇员(Employee)包括经理(Manager),技术人员(Technician)、销售员(Salesman)和销售部经理(SalesManager)。要求存储这些人员的姓名、编号、级别、当月薪水,计算月薪并显示全部信息。程序要对所有人员有提升级别的功能。为简单起见，所有人员的初始级别均为 1，然后进行升级,经理升为4级,技术人员和销售部经理升为3级,销售员仍为1级。月薪计算办法是：经理拿固定月薪 8000 元，技术人员按每小时 100 元领取月薪，销售员按该当月销售额4%提成,销售经理既拿固定月工资也领取销售提成,固定月工资为5000元,销售提成为所管辖部门当月销售额的 5‰。

#include <iostream>
#include <string>
using namespace std;

class Employee
{
protected:
  string name;
  int id;
  int level;
  float monthlySalary;

public:
  Employee(string name, int id)
  {
    this->name = name;
    this->id = id;
    this->level = 1;
    this->monthlySalary = 0;
  }

  void display()
  {
    cout << "姓名：" << name << endl;
    cout << "编号：" << id << endl;
    cout << "级别：" << level << endl;
    cout << "当月薪水：" << monthlySalary << "元" << endl;
  }
};

class Manager : public Employee
{
public:
  Manager(string name, int id) : Employee(name, id)
  {
    monthlySalary = 8000;
  }
  void promote()
  {
    level = 4;
  }
};

class Technician : public Employee
{
private:
  int workedHours;

public:
  Technician(string name, int id) : Employee(name, id)
  {
    monthlySalary = 0;
    workedHours = 0;
  }

  void setWorkedHours(int hours)
  {
    workedHours = hours;
    monthlySalary = workedHours * 100;
  }
  void promote()
  {
    level = 3;
  }
};

class Salesman : public Employee
{
private:
  float salesAmount;

public:
  Salesman(string name, int id) : Employee(name, id)
  {
    monthlySalary = 0;
    salesAmount = 0;
  }

  void setSalesAmount(float amount)
  {
    salesAmount = amount;
    monthlySalary = salesAmount * 0.04;
  }
  void promote()
  {
    level = 1;
  }
};

class SalesManager : public Employee
{
private:
  float salesAmount;

public:
  SalesManager(string name, int id) : Employee(name, id)
  {
    monthlySalary = 5000;
    salesAmount = 0;
  }

  void setSalesAmount(float amount)
  {
    salesAmount = amount;
    monthlySalary += salesAmount * 0.005;
  }
  void promote()
  {
    level = 3;
  }
};

int main()
{
  // 创建员工对象
  Manager manager("经理", 1);
  Technician technician("技术人员", 2);
  Salesman salesman("销售员", 3);
  SalesManager salesManager("销售部经理", 4);

  // 设置员工的相关信息
  technician.setWorkedHours(80);
  salesman.setSalesAmount(20000);
  salesManager.setSalesAmount(50000);

  // 显示员工信息
  cout << "经理信息：" << endl;
  manager.display();
  cout << endl;

  cout << "技术人员信息：" << endl;
  technician.display();
  cout << endl;

  cout << "销售员信息：" << endl;
  salesman.display();
  cout << endl;

  cout << "销售部经理信息：" << endl;
  salesManager.display();
  cout << endl;

  // 提升级别
  manager.promote();
  technician.promote();
  salesManager.promote();

  // 显示提升后的员工信息
  cout << "提升后的经理信息：" << endl;
  manager.display();
  cout << endl;

  cout << "提升后的技术人员信息：" << endl;
  technician.display();
  cout << endl;

  cout << "提升后的销售员信息：" << endl;
  salesman.display();
  cout << endl;

  cout << "提升后的销售部经理信息：" << endl;
  salesManager.display();
  cout << endl;

  return 0;
}