实验5 继承和多态
task3
pets.hpp
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#pragma once
#include <iostream>
#include <string>
using std::cout;
using std::endl;
using std::string;
class MachinePets{
public:
MachinePets(const string &s):nickname(s){}
string get_nickname() const{ return nickname;}
virtual string talk()=0;
private:
string nickname;
};
class PetCats:public MachinePets{
public:
PetCats(const string &s):MachinePets(s){}
string talk(){
return "miao wu~";
}
};
class PetDogs:public MachinePets{
public:
PetDogs(const string &s):MachinePets(s){}
string talk(){
return "wang wang~";
}
};
task3.cpp
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#include <iostream>
#include <vector>
#include "pets.hpp"
void test() {
using namespace std;
vector<MachinePets *> pets;
pets.push_back(new PetCats("miku"));
pets.push_back(new PetDogs("da huang"));
for(auto &ptr: pets)
cout <<ptr->get_nickname() << " says " << ptr->talk() << endl;
}
int main() {
test();
}
task4
film.hpp
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#pragma once
#include <string>
#include <iostream>
#include <iomanip>
using namespace std;
class Film{
private:
string name;
string director;
string country;
string year;
public:
friend istream& operator>>(istream& in,Film& film );
friend ostream& operator<<(ostream& cout ,const Film& film);
string get_year() const;
};
istream& operator >>(istream& in,Film& film){
cout<<"录入片名:";
in>>film.name;
cout<<"录入导演名:";
in>>film.director;
cout<<"录入制片国家:";
in>>film.country;
cout<<"录入上映年份:";
in >>film.year;
return in;
}
ostream& operator <<(ostream& out,const Film& film )
{
out<<left;
out<<setw(20)<<film.name<<setw(10)<<film.director<<setw(10)<<film.country<<setw(10)<<film.year;
return out;
}
string Film::get_year() const{
return year;
}
bool compare_by_year(const Film& f1, const Film& f2) {
return f1.get_year() < f2.get_year();
}
task4.cpp
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#include "film.hpp"
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
void test() {
using namespace std;
int n;
cout << "输入电影数目: ";
cin >> n;
cout << "录入" << n << "部影片信息" << endl;
vector<Film> film_lst;
for(int i = 0; i < n; ++i) {
Film f;
cout << string(20, '-') << "第" << i+1 << "部影片录入" << string(20, '-') << endl;
cin >> f;
film_lst.push_back(f);
}
// 按发行年份升序排序
sort(film_lst.begin(), film_lst.end(), compare_by_year);
cout << string(20, '=') + "电影信息(按发行年份)" + string(20, '=')<< endl;
for(auto &f: film_lst)
cout << f << endl;
}
int main() {
test();
}
task5
complex.hpp
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#pragma once
#include <iostream>
#include <string>
#include<iomanip>
using namespace std;
template <typename T>
class Complex{
private:
T real;
T imag;
public:
Complex(T r=0.0,T i=0.0):real(r),imag(i){}
Complex(const Complex &c);
Complex operator+(const Complex &c) {
return Complex(real+c.real,imag+c.imag);
}
Complex operator-(const Complex &c) {
return Complex(real-c.real,imag-c.imag);
}
Complex& operator+=(const Complex &c){
real+=c.real;
imag+=c.imag;
return *this;
}
T get_real();
T get_imag();
friend bool operator==(const Complex &c1,const Complex &c2) {
if((c1.real==c2.real)&&(c1.imag==c2.imag))
return true;
else
return false;
}
friend istream& operator>>(istream& in,Complex& c){
in>>c.real>>c.imag;
return in;
}
friend ostream& operator<<(ostream& out,const Complex& c){
if(c.imag>0)
{
out<<left;
out<<c.real<<"+"<<c.imag<<"i";
}
else
{
out<<left;
out<<c.real<<c.imag<<"i";
}
return out;
}
};
template <typename T>
Complex<T>::Complex(const Complex &c) {
real=c.real;
imag=c.imag;
}
template <typename T>
T Complex<T>::get_imag() {
return imag;
}
template <typename T>
T Complex<T>::get_real() {
return real;
}
task5.cpp
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#include "Complex.hpp"
#include <iostream>
using std::cin;
using std::cout;
using std::endl;
using std::boolalpha;
void test1() {
Complex<int> c1(2, -5), c2(c1);
cout << "c1 = " << c1 << endl;
cout << "c2 = " << c2 << endl;
cout << "c1 + c2 = " << c1 + c2 << endl;
c1 += c2;
cout << "c1 = " << c1 << endl;
cout << boolalpha << (c1 == c2) << endl;
}
void test2() {
Complex<double> c1, c2;
cout << "Enter c1 and c2: ";
cin >> c1 >> c2;
cout << "c1 = " << c1 << endl;
cout << "c2 = " << c2 << endl;
cout << "c1.real = " << c1.get_real() << endl;
cout << "c1.imag = " << c1.get_imag() << endl;
}
int main() {
cout << "自定义类模板Complex测试1: " << endl;
test1();
cout << endl;
cout << "自定义类模板Complex测试2: " << endl;
test2();
}
task6
data.h
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#pragma once
class Date {
private:
int year;
int month;
int day;
int totalDays;
public:
Date(int year, int month, int day);
int getYear() const {
return year;
}
int getMonth() const {
return month;
}
int getDay() const {
return day;
}
int getMaxDay() const;
bool isLeapYear() const {
return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}
void show() const;
int operator-(const Date& date) const {
return totalDays - date.totalDays;
}
};
data.cpp
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#include "date.h"
#include <iostream>
#include <cstdlib>
using namespace std;
namespace {
const int DAYS_BEFIRE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };
}
Date::Date(int year, int month, int day) : year(year), month(month), day(day) {
if (day <= 0 || day > getMaxDay()) {
cout << "Invalid date: ";
show();
cout << endl;
exit(1);
}
int years = year - 1;
totalDays = years * 365 + years / 4 - years / 100 + years / 400 + DAYS_BEFIRE_MONTH[month - 1] + day;
if (isLeapYear() && month > 2) totalDays++;
}
int Date::getMaxDay() const {
if (isLeapYear() && month == 2)
return 29;
else
return DAYS_BEFIRE_MONTH[month] - DAYS_BEFIRE_MONTH[month - 1];
}
void Date::show() const {
cout << getYear() << "-" << getMonth() << "-" << getDay();
}
account.h
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#pragma once
#include "date.h"
#include "accumulator.h"
#include <string>
using namespace std;
class Account {
private:
string id;
double balance;
static double total;
protected:
Account(const Date& date, const string &id);
void record(const Date& date, double amount, const string& desc);
void error(const string& msg) const;
public:
const string& getId() {
return id;
}
double getBalance() const {
return balance;
}
static double getTotal() {
return total;
}
virtual void deposit(const Date& date, double amount, const string& desc) = 0;
virtual void withdraw(const Date& date, double amount, const string& desc) = 0;
virtual void settle(const Date& date) = 0;
virtual void show() const;
};
class SavingsAccount : public Account {
private:
Accumulator acc;
double rate;
public:
SavingsAccount(const Date& date, const string& id, double rate);
double getRate() const {
return rate;
}
void deposit(const Date& date, double amount, const string& desc);
void withdraw(const Date& date, double amount, const string& desc);
void settle(const Date& date);
};
class CreditAccount : public Account {
private:
Accumulator acc;
double credit;
double rate;
double fee;
double getDebt() const {
double balance = getBalance();
return (balance < 0 ? balance : 0);
}
public:
CreditAccount(const Date& date, const string& id, double credit, double rate, double fee);
double getCredit() const {
return credit;
}
double getRate() const {
return rate;
}
double getFee() const {
return fee;
}
double getAvailableCredit() const {
if (getBalance() < 0) return credit + getBalance();
else return credit;
}
void deposit(const Date& date, double amount, const string& desc);
void withdraw(const Date& date, double amount, const string& desc);
void settle(const Date& date);
void show() const;
};
account.cpp
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#include "account.h"
#include <cmath>
#include <iostream>
using namespace std;
double Account::total = 0;
Account::Account(const Date& date, const string& id) : id(id), balance(0) {
date.show();
cout << "\t#" << id << " created" << endl;
}
void Account::record(const Date& date, double amount, const string& desc) {
amount = floor(amount * 100 + 0.5) / 100;
balance += amount;
total += amount;
date.show();
cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl;
}
void Account::show() const {
cout << id << "\tBalance:" << balance;
}
void Account::error(const string& msg) const {
cout << "Error(#" << id << "):" << msg << endl;
}
SavingsAccount::SavingsAccount(const Date& date, const string& id, double rate)
: Account(date, id), rate(rate), acc(date, 0) {}
void SavingsAccount::deposit(const Date& date, double amount, const string& desc) {
record(date, amount, desc);
acc.change(date, getBalance());
}
void SavingsAccount::withdraw(const Date& date, double amount, const string& desc) {
if (amount > getBalance()) {
error("not enough money");
} else {
record(date, -amount, desc);
acc.change(date, getBalance());
}
}
void SavingsAccount::settle(const Date& date) {
double interest = acc.getSum(date) * rate / (date - Date(date.getYear() - 1, 1, 1));
if (interest != 0) record(date, interest, "interest");
acc.reset(date, getBalance());
}
CreditAccount::CreditAccount(const Date& date, const string& id, double credit, double rate, double fee)
: Account(date, id), credit(credit), rate(rate), fee(fee), acc(date, 0) {}
void CreditAccount::deposit(const Date& date, double amount, const string& desc) {
record(date, amount, desc);
acc.change(date, getDebt());
}
void CreditAccount::withdraw(const Date& date, double amount, const string& desc) {
if (amount - getBalance() > credit) {
error("not enough credit");
} else {
record(date, -amount, desc);
acc.change(date, getDebt());
}
}
void CreditAccount::settle(const Date& date) {
double interest = acc.getSum(date) * rate;
if (interest != 0) record(date, interest, "interest");
if (date.getMonth() == 1) record(date, -fee, "annual fee");
acc.reset(date, getDebt());
}
void CreditAccount::show() const {
Account::show();
cout << "\tAvailable credit:" << getAvailableCredit();
}
test6.cpp
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#include"account.h"
#include<iostream>
using namespace std;
int main() {
Date date(2008, 11, 1);
SavingsAccount sa1(date, "S3755217", 0.015);
SavingsAccount sa2(date, "02342342", 0.015);
CreditAccount ca(date, "C5392394", 10000, 0.0005, 50);
Account* accounts[] = { &sa1,&sa2,&ca };
const int n = sizeof(accounts) / sizeof(Account*);
cout << "(d)deposit (w)withdraw (s)show (c)change day (n)next month (e)exit" << endl;
char cmd;
do {
date.show();
cout << "\tTotal:" << Account::getTotal() << "\tcommand>";
int index, day;
double amount;
string desc;
cin >> cmd;
switch (cmd) {
case 'd':
cin >> index >> amount;
getline(cin, desc);
accounts[index]->deposit(date, amount, desc);
break;
case 'w':
cin >> index >> amount;
getline(cin, desc);
accounts[index]->withdraw(date, amount, desc);
break;
case 's':
for (int i = 0; i < n; i++) {
cout << "[" << i << "]";
accounts[i]->show();
cout << endl;
}
break;
case 'c':
cin >> day;
if (day < date.getDay()) {
cout << "You cannot specify a previous day";
} else if (day > date.getMaxDay())
cout << "Invalid day";
else date = Date(date.getYear(), date.getMonth(), day);
break;
case 'n':
if (date.getMonth() == 12)
date = Date(date.getYear() + 1, 1, 1);
else date = Date(date.getYear(), date.getMonth() + 1, 1);
for (int i = 0; i < n; i++) {
accounts[i]->settle(date);
}
break;
}
} while (cmd != 'e');
return 0;
}

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