实验2
x.h
#include <iostream>
#include <math.h>
#include <string>
using namespace std;
using std::string;
class T
{
public:
T(int x = 0, int y = 0);
T(const T &t);
T(T &&t);
~T();
static int get_cnt(); // 显示当前T类对象总数
static const std::string doc; // 类T的描述信息
static const int max_cnt; // 类T对象上限
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;
static int cnt; // 当前T类对象数目
friend void func();
};
void func();
x.cpp
#include <iostream>
#include <math.h>
#include <string>
#include "x.h"
using namespace std;
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;
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 << ")" ;}
int T::get_cnt() {return cnt;}
void func()
{
T t5(42);
t5.m2 = 2049;
cout << "t5 = "; t5.display(); cout << endl;
}
main.cpp
#include <iostream>
#include "x.h"
using std::cout;
using std::endl;
using std::boolalpha;
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();
}
能
析构函数在文件最后被调用
不能
x.h
#include <iostream> #include <math.h> #include <string> using namespace std; using std::string; class Complex { private: double r; double i; public: static const string doc; Complex(double A=0,double B=0); Complex(const Complex &t); ~Complex(); double get_real(); double get_imag(); void add(const Complex &t); friend Complex add(const Complex &a,const Complex &b); friend bool is_equal(const Complex &a,const Complex &b); friend bool is_not_equal(const Complex &a,const Complex &b); friend void output(const Complex &a); friend double abs(const Complex &a); };
x.cpp
#include <iostream> #include <math.h> #include <string> #include "x.h" using namespace std; using std::string; const string Complex::doc = "a simplified Complex class"; //---------------------------------------------------------------- Complex::Complex(double A,double B): r{A},i{B} {} Complex::Complex(const Complex &t): r{t.r},i{t.i} {} Complex::~Complex() {} double Complex::get_real() { return r; } double Complex::get_imag() { return i; } void Complex::add(const Complex &t) { r+=t.r; i+=t.i; } //------------------------------------------------------------------ Complex add(const Complex &a,const Complex &b) { double dr = a.r + b.r; double di = a.i + b.i; return Complex(dr,di); } bool is_equal(const Complex &a,const Complex &b) { if( a.r==b.r && a.i==b.i) return true; else return false; } bool is_not_equal(const Complex &a,const Complex &b) { if( a.r==b.r && a.i==b.i) return false; else return true; } void output(const Complex &a) { if(a.i>=0) cout << a.r << " + " << a.i << "i"; else cout << a.r << " - " << -a.i << "i"; } double abs(const Complex &a) { return sqrt(a.r*a.r+a.i*a.i); }
main.cpp
#include <iostream> #include "x.h" 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(); }
#include <iostream> #include <complex> //引用标准库模板类complex using std::cout; using std::endl; using std::boolalpha; using std::complex; void test() { cout << "标准库模板类complex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(); }
x.h
#include <iostream> #include <math.h> #include <string> using namespace std; using std::string; class Fraction { private: int up; int down; public: static const string doc; Fraction(int A,int B=1); Fraction(const Fraction &t); ~Fraction(); int get_up(); int get_down(); Fraction negative(); friend void output(const Fraction &a); friend Fraction add(const Fraction &a,const Fraction &b); friend Fraction sub(const Fraction &a,const Fraction &b); friend Fraction mul(const Fraction &a,const Fraction &b); friend Fraction div(const Fraction &a,const Fraction &b); };
x.cpp
#include <iostream> #include <math.h> #include <string> #include "x.h" using namespace std; using std::string; 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.\n"; Fraction::Fraction(int A,int B): up{A},down{B} { if(down<0 && up>0) { down = -down; up = -up; int n = (-up)<down? (-up):down; for(n-=1; n>1; n--) if(up%n==0 && down%n==0) { up/=n; down/=n; } } else if(down<0 && up<0) { down = -down; up = -up; int n = up<down? up:down; for(n-=1; n>1; n--) if(up%n==0 && down%n==0) { up/=n; down/=n; } } else { int n = (-up)<down? (-up):down; for(n-=1; n>1; n--) if(up%n==0 && down%n==0) { up/=n; down/=n; } } } Fraction::Fraction(const Fraction &t): up{t.up},down{t.down} {} Fraction::~Fraction() {} int Fraction::get_up() { return up; } int Fraction::get_down() { return down; } Fraction Fraction::negative() { int Nup,Ndown; Nup = -up; Ndown = down; return Fraction(Nup,Ndown); } void output(const Fraction &a) { if(a.down==0) cout << "分母不能为0"; else if(a.up==0) cout << "0"; else if(a.down==1) cout << a.up; else cout << a.up << "/" << a.down; } Fraction add(const Fraction &a,const Fraction &b) { int dup = a.up*b.down + b.up*a.down; int ddown = a.down*b.down; return Fraction(dup,ddown); } Fraction sub(const Fraction &a,const Fraction &b) { int dup = a.up*b.down - b.up*a.down; int ddown = a.down*b.down; return Fraction(dup,ddown); } Fraction mul(const Fraction &a,const Fraction &b) { int dup = a.up*b.up; int ddown = a.down*b.down; return Fraction(dup,ddown); } Fraction div(const Fraction &a,const Fraction &b) { int dup = a.up*b.down; int ddown = a.down*b.up; return Fraction(dup,ddown); } /* */
main.cpp
#include <iostream> #include "x.h" using std::cout; using std::endl; using std::boolalpha; 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(); } /* */
x.h
#include <iostream> #include <math.h> #include <string> using namespace std; using std::string; 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积值 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 amount);//存入现金 void withdraw(int date, double amount);//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; };
x.cpp
#include <iostream> #include <cmath> #include <string> #include "x.h" using namespace std; using std::string; double SavingsAccount::total=0; //SavingsAccount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 enough money"<<endl; else record(date, -amount); } void SavingsAccount::settle (int date) {//计算年息 double interest=accumulate (date) * rate/365; if (interest !=0) record(date, interest); accumulation=0; } void SavingsAccount::show() const { cout<<"#"<<id<<"\tBalance: "<<balance; }
main.cpp
#include <iostream> #include "x.h" using std::cout; using std::endl; using std::boolalpha; int main() { //建立几个账户 SavingsAccount sa0(1, 21325302, 0.015); SavingsAccount sal(1, 58320212, 0.015); //几笔账目 sa0.deposit(5, 5000); sal.deposit(25, 10000); sa0.deposit(45, 5500); sal.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); sal.settle(90); //输出各个账户信息 sa0.show(); cout<<endl; sal.show(); cout<<endl; cout<<"Total: "<<SavingsAccount::getTotal()<<endl; return 0; }