实验2 类和对象_基础编程1
- 实验任务1：
- 源码：t.h
#pragma once #include <string> // 类T: 声明 class T { // 对象属性、方法 public: T(int x = 0, int y = 0); // 普通构造函数 T(const T &t); // 复制构造函数 T(T &&t); // 移动构造函数 ~T(); // 析构函数 void adjust(int ratio); // 按系数成倍调整数据 void display() const; // 以(m1, m2)形式显示T类对象信息 private: int m1, m2; // 类属性、方法 public: static int get_cnt(); // 显示当前T类对象总数 public: static const std::string doc; // 类T的描述信息 static const int max_cnt; // 类T对象上限 private: static int cnt; // 当前T类对象数目 // 类T友元函数声明 friend void func(); }; // 普通函数声明 void func();
t.cpp
// 类T: 实现 // 普通函数实现 #include "t.h" #include <iostream> #include <string> using std::cout; using std::endl; using std::string; // static成员数据类外初始化 const std::string T::doc{"a simple class sample"}; const int T::max_cnt = 999; int T::cnt = 0; // 对象方法 T::T(int x, int y): m1{x}, m2{y} { ++cnt; cout << "T constructor called.\n"; } T::T(const T &t): m1{t.m1}, m2{t.m2} { ++cnt; cout << "T copy constructor called.\n"; } T::T(T &&t): m1{t.m1}, m2{t.m2} { ++cnt; cout << "T move constructor called.\n"; } T::~T() { --cnt; cout << "T destructor called.\n"; } void T::adjust(int ratio) { m1 *= ratio; m2 *= ratio; } void T::display() const { cout << "(" << m1 << ", " << m2 << ")" ; } // 类方法 int T::get_cnt() { return cnt; } // 友元 void func() { T t5(42); t5.m2 = 2049; cout << "t5 = "; t5.display(); cout << endl; }
task1.cpp
#include "t.h" #include <iostream> using std::cout; using std::endl; void test(); int main() { test(); cout << "\nmain: \n"; cout << "T objects'current count: " << T::get_cnt() << endl; } void test() { cout << "test class T: \n"; cout << "T info: " << T::doc << endl; cout << "T objects'max count: " << T::max_cnt << endl; cout << "T objects'current count: " << T::get_cnt() << endl << endl; T t1; cout << "t1 = "; t1.display(); cout << endl; T t2(3, 4); cout << "t2 = "; t2.display(); cout << endl; T t3(t2); t3.adjust(2); cout << "t3 = "; t3.display(); cout << endl; T t4(std::move(t2)); cout << "t3 = "; t4.display(); cout << endl; cout << "T objects'current count: " << T::get_cnt() << endl; func(); }
运行结果截图：
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- 问题1：
缺少了void func对函数的定义 仅在类中声明了友元函数 无法实现其功能
-
- 问题2：普通构造函数：创建对象时初始化对象并分配资源 、
复制构造函数：创建一个新对象，并将现有对象的状态复制到新对象中
移动构造函数：移动对象而不是复制
在所有操作 程序结束后对象不再进行操作后实现析构函数
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- 问题3：不能编译运行
- 实验任务2：
Complex.h
#pragma once
#include<iostream>
#include<vector>
#include<string>
class Complex{
public:
static const std::string doc;
Complex(double r=0,double i=0);
Complex(const Complex &other);
~Complex();
add(const Complex &other);
private:
double imag,real;
public:
double get_real() const;
double get_imag() const;
friend Complex add(const Complex &c1,const Complex &c2);
friend bool is_equal(const Complex c1,const Complex c2);
friend bool is_not_equal(const Complex c1,const Complex c2);
friend void output(const Complex &c);
friend double abs(const Complex c);
};
Complex.cpp
#include "Complex.h"
#include<iostream>
#include<string>
#include<cmath>
using std::cout;
using std::endl;
using std::string;
using std::boolalpha;
Complex::Complex(double r,double i):real(r),imag(i){}
Complex::Complex(const Complex &other){
real=other.real;
imag=other.imag;
}
double Complex::get_real() const{
return real;
}
double Complex::get_imag() const{
return imag;
}
bool is_equal(const Complex c1,const Complex c2){
if(c1.real==c2.real&&c1.imag==c2.imag)
return true;
else
return false;
}
bool is_not_equal(const Complex c1,const Complex c2){
if(c1.real!=c2.real||c1.imag!=c2.imag)
return true;
else
return false;
}
Complex::add(const Complex &other){
real+=other.real;
imag+=other.imag;
}
Complex add(const Complex &c1,const Complex &c2){
Complex sum(0,0);
sum.real=c1.real+c2.real;
sum.imag=c1.imag+c2.imag;
return sum;
}
void output(const Complex &c){
cout<<c.real<<"+"<<c.imag<<"i"<<endl;
}
double abs(const Complex c){
double h;
h=sqrt(c.real*c.real+c.imag*c.imag);
return h;
}
const std::string Complex::doc{"a simplified complex class"};
Complex::~Complex(){}
task2.cpp
#include "Complex.h" #include <iostream> #include <cmath> using std::cout; using std::endl; using std::boolalpha; void test() { cout << "类成员测试: " << endl; cout << Complex::doc << endl; cout << endl; cout << "Complex对象测试: " << endl; Complex c1; Complex c2(3, -4); const Complex c3(3.5); Complex c4(c3); cout << "c1 = "; output(c1); cout << endl; cout << "c2 = "; output(c2); cout << endl; cout << "c3 = "; output(c3); cout << endl; cout << "c4 = "; output(c4); cout << endl; cout << "c4.real = " << c4.get_real() << ", c4.imag = " << c4.get_imag() << endl; cout << endl; cout << "复数运算测试: " << endl; cout << "abs(c2) = " << abs(c2) << endl; c1.add(c2); cout << "c1 += c2, c1 = "; output(c1); cout << endl; cout << boolalpha; cout << "c1 == c2 : " << is_equal(c1, c2) << endl; cout << "c1 != c3 : " << is_not_equal(c1, c3) << endl; c4 = add(c2, c3); cout << "c4 = c2 + c3, c4 = "; output(c4); cout << endl; } int main(){ test(); }
运行代码截图:
- 实验任务3：
#include <iostream>
#include <complex>
using std::cout;
using std::endl;
using std::boolalpha;
using std::complex;
void test() {
cout << "标准库模板类comple测试: " << endl;
complex<double> c1;
complex<double> c2(3, -4);
const complex<double> c3(3.5);
complex<double> c4(c3);
cout << "c1 = " << c1 << endl;
cout << "c2 = " << c2 << endl;
cout << "c3 = " << c3 << endl;
cout << "c4 = " << c4 << endl;
cout << "c4.real = " << c4.real() << ", c4.imag = " << c4.imag() << endl;
cout << endl;
cout << "复数运算测试: " << endl;
cout << "abs(c2) = " << abs(c2) << endl;
c1 += c2;
cout << "c1 += c2, c1 = " << c1 << endl;
cout << boolalpha;
cout << "c1 == c2 : " << (c1 == c2) << endl;
cout << "c1 != c3 : " << (c1 != c3) << endl;
c4 = c2 + c3;
cout << "c4 = c2 + c3, c4 = " << c4 << endl;
}
int main() {
test();
}
运行结果截图：
有求实数和虚数的接口 还有取模长 判断是否相等 和复数相加的运算
- 实验任务4：
Fraction.h
#pragma once #include<iostream> #include<string> #include<cstdlib> class Fraction{ public: static const std::string doc; Fraction(int u,int d); Fraction(int u); Fraction(); Fraction(const Fraction &f); ~Fraction(); int get_up() const; int get_down() const; Fraction negative(); private: int up,down; public: friend void output(const Fraction f); friend Fraction add(const Fraction f1,const Fraction f2); friend Fraction sub(const Fraction f1,const Fraction f2); friend Fraction mul(const Fraction f1,const Fraction f2); friend Fraction div(const Fraction f1,const Fraction f2); };
Fraction.cpp
#include"Fraction.h" #include<iostream> #include<string> #include<cmath> using std::cout; using std::endl; using std::string; Fraction::Fraction(){ up=1; down=1; } Fraction::Fraction(int u,int d){ up=u; down=d; } Fraction::Fraction(int u){ up=u; down=1; } Fraction::Fraction(const Fraction &f){ up=f.up; down=f.down; } const string Fraction::doc{"Fraction类 v 0.01版.\n目前仅支持分数对象的构造、输出、加/减/乘/除运算"}; int Fraction::get_up()const{ if(!up && down) return 0; else if(down){ int up1=up,down1=down; int r=up1%down1; while(r){ up1=down1; down1=r; r=up1%down1; } r=down1; up1=up/r; return up1; } } int Fraction::get_down()const{ if(down){ int up1=up,down1=down; int r=up1%down1; while(r){ up1=down1; down1=r; r=up1%down1; } r=down1; down1=down/r; return down1; } } Fraction Fraction::negative(){ Fraction f1; f1.up=-up; f1.down=down; return f1; } void output(Fraction f){ int up1=f.get_up(),down1=f.get_down(); if(!up1&&down1) cout<<0; else if(down1){ int flag=1; if(up1*down1<0) flag=-1; up1=abs(up1); down1=abs(down1); cout<<flag*up1<<'/'<<down1; } } Fraction add(Fraction f1,Fraction f2){ Fraction f0; int up1=f1.up,down1=f1.down,up2=f2.up,down2=f2.down; int flag1=1,flag2=1; if(up1*down1<0) flag1=-1; if(up2*down2<0) flag2=-1; up1=abs(up1); up2=abs(up2); down1=abs(down1); down2=abs(down2); int down_m; int r=down1%down2; while(r){ down1=down2; down2=r; r=down1%down2; } r=down2; down1=abs(f1.down); down2=abs(f2.down); down_m=down1*down2/r; up1*=down_m/down1; up2*=down_m/down2; f0.up=flag1*up1+flag2*up2; f0.down=down_m; return f0; } Fraction sub(Fraction f1,Fraction f2){ Fraction f0=add(f1,f2.negative()); return f0; } Fraction mul(Fraction f1,Fraction f2){ Fraction f0; f0.up=f1.up*f2.up; f0.down=f1.down*f2.down; return f0; } Fraction div(Fraction f1,Fraction f2){ Fraction f0; f0.up=f1.up*f2.down; f0.down=f1.down*f2.up; return f0; }
task4.cpp
#include "Fraction.h" #include <iostream> using std::cout; using std::endl; void test1() { cout << "Fraction类测试: " << endl; cout << Fraction::doc << endl << endl; Fraction f1(5); Fraction f2(3, -4), f3(-18, 12); Fraction f4(f3); cout << "f1 = "; output(f1); cout << endl; cout << "f2 = "; output(f2); cout << endl; cout << "f3 = "; output(f3); cout << endl; cout << "f4 = "; output(f4); cout << endl; Fraction f5(f4.negative()); cout << "f5 = "; output(f5); cout << endl; cout << "f5.get_up() = " << f5.get_up() << ", f5.get_down() = " << f5.get_down() << endl; cout << "f1 + f2 = "; output(add(f1, f2)); cout << endl; cout << "f1 - f2 = "; output(sub(f1, f2)); cout << endl; cout << "f1 * f2 = "; output(mul(f1, f2)); cout << endl; cout << "f1 / f2 = "; output(div(f1, f2)); cout << endl; cout << "f4 + f5 = "; output(add(f4, f5)); cout << endl; } void test2() { Fraction f6(42, 55), f7(0, 3); cout << "f6 = "; output(f6); cout << endl; cout << "f7 = "; output(f7); cout << endl; cout << "f6 / f7 = "; output(div(f6, f7)); cout << endl; } int main() { cout << "测试1: Fraction类基础功能测试\n"; test1(); cout << "\n测试2: 分母为0测试: \n"; test2(); }
运行结果截图:
- 实验任务5：
account.h
#ifndef __ACCOUNT_H__
#define __ACCOUNT_H__
class SavingsAccount{
private:
int id;//账号
double balance;//余额
double rate;//存款的年利率
int lastDate;//上次变更余额的时期
double accumulation;//余额按日累加之和
static double total;//所有账户的总金额
//记录一笔账，date为日期，amount为金额，desc为说明
void record (int date,double amount);
//获得到指定日期为止的存款金额按日累计值
double accumulate(int date)const{
return accumulation+balance*(date-lastDate);
}
public:
//构造函数
SavingsAccount(int date,int id,double rate);
int getId()const{return id;}
double getBalance()const {return balance;}
double getRate() const{return rate;}
static double getTotal(){return total;}
void deposit(int date,double amout);//存入现金
void withdraw(int date,double amout);//取出现金
//结算利息，每年1月1日调用一次该函数
void settle(int date);
//显示账户信息
void show() const;
};
#endif //__ACCOUNT_H__
account.cpp
#include"account.h"
#include<cmath>
#include<iostream>
using namespace std;
double SavingsAccount::total=0;
//SavingsAccouont类相关成员函数的实现
SavingsAccount::SavingsAccount(int date,int id,double rate):id(id),balance(0),rate(rate),lastDate(date),accumulation(0){
cout<<date<<"\t#"<<id<<"is created"<<endl;
}
void SavingsAccount::record(int date,double amount){
accumulation=accumulate(date);
lastDate=date;
amount=floor(amount*100+0.5)/100;
balance+=amount;
total+=amount;
cout<<date<<"\t#"<<id<<"\t"<<amount<<"\t"<<balance<<endl;
}
void SavingsAccount::deposit(int date,double amount){
record(date,amount);
}
void SavingsAccount::withdraw(int date,double amount){
if(amount>getBalance())
cout<<"Error:not enogh money"<<endl;
else
record(date,-amount);
}
void SavingsAccount::settle(int date){
double interest=accumulate(date)*rate/365;//计算年息
if(interest!=0)
record(date,interest) ;
accumulation=0;
}
void SavingsAccount::show()const{
cout<<"#"<<id<<"\tBalance:"<<balance;
}
5_11.cpp
#include"account.h"
#include<iostream>
using namespace std;
int main(){
//建立几个账户
SavingsAccount sa0(1,21325302,0.015);
SavingsAccount sa1(1,58320212,0.015);
//几笔账目
sa0.deposit(5,5000);
sa1.deposit(25,10000);
sa0.deposit(45,5500);
sa1.withdraw(60,4000);
//开户后第90天到了银行的计息日，结算所有账户的年息
sa0.settle(90);
sa1.settle(90);
//输出各个账户信息
sa0.show();cout<<endl;
sa1.show();cout<<endl;
cout<<"Total:"<<SavingsAccount::getTotal()<<endl;
return 0;
}
运行结果截图:
