实验二

任务一：

  1 t.h
  2 #pragma once
  3 
  4 #include <string>
  5 
  6 // 类T: 声明
  7 class T {
  8 // 对象属性、方法
  9 public:
 10     T(int x = 0, int y = 0);   // 普通构造函数
 11     T(const T &t);  // 复制构造函数
 12     T(T &&t);       // 移动构造函数
 13     ~T();           // 析构函数
 14 
 15     void adjust(int ratio);      // 按系数成倍调整数据
 16     void display() const;           // 以(m1, m2)形式显示T类对象信息
 17 
 18 private:
 19     int m1, m2;
 20 
 21 // 类属性、方法
 22 public:
 23     static int get_cnt();          // 显示当前T类对象总数
 24 
 25 public:
 26     static const std::string doc;       // 类T的描述信息
 27     static const int max_cnt;           // 类T对象上限
 28 
 29 private:
 30     static int cnt;         // 当前T类对象数目
 31 
 32 // 类T友元函数声明
 33     friend void func();
 34 };
 35 
 36 // 普通函数声明
 37 void func();
 38 
 39 t.cpp
 40 // 类T: 实现
 41 // 普通函数实现
 42 
 43 #include "t.h"
 44 #include <iostream>
 45 #include <string>
 46 
 47 using std::cout;
 48 using std::endl;
 49 using std::string;
 50 
 51 // static成员数据类外初始化
 52 const std::string T::doc{"a simple class sample"};
 53 const int T::max_cnt = 999;
 54 int T::cnt = 0;
 55 
 56 
 57 // 对象方法
 58 T::T(int x, int y): m1{x}, m2{y} { 
 59     ++cnt; 
 60     cout << "T constructor called.\n";
 61 } 
 62 
 63 T::T(const T &t): m1{t.m1}, m2{t.m2} {
 64     ++cnt;
 65     cout << "T copy constructor called.\n";
 66 }
 67 
 68 T::T(T &&t): m1{t.m1}, m2{t.m2} {
 69     ++cnt;
 70     cout << "T move constructor called.\n";
 71 }    
 72 
 73 T::~T() {
 74     --cnt;
 75     cout << "T destructor called.\n";
 76 }           
 77 
 78 void T::adjust(int ratio) {
 79     m1 *= ratio;
 80     m2 *= ratio;
 81 }    
 82 
 83 void T::display() const {
 84     cout << "(" << m1 << ", " << m2 << ")" ;
 85 }     
 86 
 87 // 类方法
 88 int T::get_cnt() {
 89    return cnt;
 90 }
 91 
 92 // 友元
 93 void func() {
 94     T t5(42);
 95     t5.m2 = 2049;
 96     cout << "t5 = "; t5.display(); cout << endl;
 97 }
 98 
 99 task1.cpp
100 #include "t.h"
101 #include <iostream>
102 
103 using std::cout;
104 using std::endl;
105 
106 void test();
107 
108 int main() {
109     test();
110     cout << "\nmain: \n";
111     cout << "T objects'current count: " << T::get_cnt() << endl;
112 }
113 
114 void test() {
115     cout << "test class T: \n";
116     cout << "T info: " << T::doc << endl;
117     cout << "T objects'max count: " << T::max_cnt << endl;
118     cout << "T objects'current count: " << T::get_cnt() << endl << endl;
119 
120 
121     T t1;
122     cout << "t1 = "; t1.display(); cout << endl;
123 
124     T t2(3, 4);
125     cout << "t2 = "; t2.display(); cout << endl;
126 
127     T t3(t2);
128     t3.adjust(2);
129     cout << "t3 = "; t3.display(); cout << endl;
130 
131     T t4(std::move(t2));
132     cout << "t3 = "; t4.display(); cout << endl;
133 
134     cout << "T objects'current count: " << T::get_cnt() << endl;
135 
136     func();
137 }
View Code

结果截图：

问题1：
t.h中，普通函数 func 作为类X的友元，在类的内部声明了友元关系。在类外部，去掉line36，重
新编译，是否能正确运行。如果能，回答说明可以去掉line36。如果不能，以截图形式给出编译报
错信息，分析可能的原因。

答：不能，友元函数func没有被单独声明。

问题2：
t.h中，line9-12给出了各种构造函数、析构函数。总结各种构造函数的功能，以及它们与析构函数
的调用时机。

答：普通构造函数：对m1,m2赋值。在每次创建新对象时被调用， 用来初始化对象。

复制构造函数：复制另一个对象的m1,m2值给当前对象的m1,m2。在 T t3(t2)；这一句被调用。

移动构造函数：在T t4(std::move(t2));这一句被调用。

析构函数：对象被删除前自动调用，依次是t1,t2,t3,t4的析构函数被调用，最后是友元函数func的析构函数被调用。

问题3：
t.cpp中，line13-15，调整到t.h，重新编译，程序能否正确编译运行。

答：可以。

 

任务二：

Complex.h

 1 #pragma once
 2 #include<vector>
 3 #include<string>
 4 #include <iostream>
 5 
 6 class Complex{
 7     public:
 8         Complex (double a=0,double b=0);
 9         Complex (const Complex &other);
10         add(const Complex &other);
11     private:
12         double real;//实部
13         double imag;//虚部 
14     public:
15         static const std::string doc;
16         double get_real() const;
17         double get_imag() const;
18         friend bool is_equal(const Complex c1,const Complex c2);
19         friend bool is_not_equal(const Complex c1,const Complex c2);
20         friend Complex add(const Complex &c1,const Complex &c2);
21         friend void output(const Complex &c);
22         friend double abs(const Complex c);
23         ~Complex();
24 };
View Code

Complex.cpp

 1 #include "Complex.h"
 2 #include<cmath>
 3 #include <iostream>
 4 #include<string>
 5 using std::cout;
 6 using std::endl;
 7 using std::boolalpha;
 8 
 9 Complex::Complex(double a,double b):real{a},imag{b} {}
10 
11 Complex::Complex(const Complex &other)
12 {
13     real=other.real;imag=other.imag;
14 }
15 
16 const std::string Complex::doc{"a simplified complex class"};
17 
18 double Complex::get_real() const{return real;}
19 
20 double Complex::get_imag() const{return imag;}
21 
22 bool is_equal(const Complex c1,const Complex c2)
23 {
24     if(c1.real==c2.real&&c1.imag==c2.imag)
25         return 1;
26     else
27         return 0;
28 }
29 
30 bool is_not_equal(const Complex c1,const Complex c2)
31 {
32     if(c1.real!=c2.real||c1.imag!=c2.imag)
33         return 1;
34     else
35         return 0;
36 }
37 
38 Complex::add(const Complex &other)
39 {
40     real=other.real+real;
41     imag=other.imag+imag;
42 }
43 
44 Complex add(const Complex &c1,const Complex &c2)
45 {
46     Complex sum(0,0);
47     sum.real=c1.real+c2.real;
48     sum.imag=c1.imag+c2.imag;
49     return sum;
50 }
51 void output(const Complex &c)
52 {
53     cout<<c.real<<"+"<<c.imag<<"i"<<endl;
54 }
55 
56 double abs(const Complex c)
57 {
58     double h;
59     h=sqrt(c.real*c.real+c.imag*c.imag);
60     return h;
61 }
62 
63 Complex::~Complex() {}
View Code

 task 2.cpp

 1 #include "Complex.h"
 2 #include <iostream>
 3 #include <cmath>
 4 
 5 using std::cout;
 6 using std::endl;
 7 using std::boolalpha;
 8 
 9 void test() {
10     cout << "类成员测试: " << endl;
11     cout << Complex::doc << endl;
12 
13     cout << endl;
14 
15     cout << "Complex对象测试: " << endl;
16     Complex c1;
17     Complex c2(3, -4);
18     const Complex c3(3.5);
19     Complex c4(c3);
20 
21     cout << "c1 = "; output(c1); cout << endl;
22     cout << "c2 = "; output(c2); cout << endl;
23     cout << "c3 = "; output(c3); cout << endl;
24     cout << "c4 = "; output(c4); cout << endl;
25     cout << "c4.real = " << c4.get_real() << ", c4.imag = " << c4.get_imag() << endl;
26 
27     cout << endl;
28 
29     cout << "复数运算测试: " << endl;
30     cout << "abs(c2) = " << abs(c2) << endl;
31     c1.add(c2);
32     cout << "c1 += c2, c1 = "; output(c1); cout << endl;
33     cout << boolalpha;
34     cout << "c1 == c2 : " << is_equal(c1, c2) << endl;
35     cout << "c1 != c3 : " << is_not_equal(c1, c3) << endl;
36     c4 = add(c2, c3);
37     cout << "c4 = c2 + c3, c4 = "; output(c4); cout << endl;
38 }
View Code

 

 任务三：

 1 #include <iostream>
 2 #include <complex>
 3 
 4 using std::cout;
 5 using std::endl;
 6 using std::boolalpha;
 7 using std::complex;
 8 
 9 void test() {
10     cout << "标准库模板类complex测试: " << endl;
11     complex<double> c1;
12     complex<double> c2(3, -4);
13     const complex<double> c3(3.5);
14     complex<double> c4(c3);
15 
16     cout << "c1 = " << c1 << endl;
17     cout << "c2 = " << c2 << endl;
18     cout << "c3 = " << c3 << endl;
19     cout << "c4 = " << c4 << endl;
20     cout << "c4.real = " << c4.real() << ", c4.imag = " << c4.imag() << endl;
21     cout << endl;
22 
23     cout << "复数运算测试: " << endl;
24     cout << "abs(c2) = " << abs(c2) << endl;
25     c1 += c2;
26     cout << "c1 += c2, c1 = " << c1 << endl;
27     cout << boolalpha;
28     cout << "c1 == c2 : " << (c1 == c2) << endl;
29     cout << "c1 != c3 : " << (c1 != c3) << endl;
30     c4 = c2 + c3;
31     cout << "c4 = c2 + c3, c4 = " << c4 << endl;
32 }
33 
34 int main() {
35     test();
36 }
View Code

 使用了接口abs，运算功能+，判断功能==和！=

任务四：

fraction.h

 1 #pragma once
 2 #include<string>
 3 #include<iostream>
 4 
 5 using std::string;
 6 
 7 class Fraction{
 8     public:
 9         static const string doc;
10         Fraction(int a,int b=1);
11         Fraction(const Fraction &f);
12         ~Fraction();
13         int get_up() const;
14         int get_down() const;
15         Fraction negative();
16     private:
17         int up,down;
18     public:
19         friend void output(Fraction a);
20         friend Fraction add(const Fraction f1,const Fraction f2);
21         friend Fraction sub(const Fraction f1,const Fraction f2);
22         friend Fraction mul(const Fraction f1,const Fraction f2);
23         friend Fraction div(const Fraction f1,const Fraction f2);
24 };
25 
26 void output(Fraction a);
27 Fraction add(const Fraction f1,const Fraction f2);
28 Fraction sub(const Fraction f1,const Fraction f2);
29 Fraction mul(const Fraction f1,const Fraction f2);
30 Fraction div(const Fraction f1,const Fraction f2);
View Code

fraction.cpp

 1 #include "Fraction.h"
 2 #include<iostream>
 3 #include<string>
 4 #include<cmath>
 5 
 6 using std::cout;
 7 using std::endl;
 8 using std::string;
 9 
10 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.";
11 
12 Fraction::~Fraction() {}
13 
14 Fraction::Fraction(int a,int b):up{a},down{b} {}
15 
16 Fraction::Fraction(const Fraction &f){
17     up=f.up;
18     down=f.down;
19 }
20 
21 int Fraction::get_up() const{
22     return up;
23 }
24 
25 int Fraction::get_down() const{
26     return down;
27 }
28 
29 Fraction Fraction::negative(){
30     Fraction f(0,0);
31     f.up=-up;
32     f.down=down;
33     return f;
34 }
35 
36 void output(Fraction a){
37     int i,u=a.up,d=a.down;
38     for(i=2;i<=9;i++){
39         if(u%i==0&&d%i==0){
40             u/=i;
41             d/=i;
42         }
43     }
44     if((u<0&&d<0)||(u>0&&d<0))
45     {
46         u=-u;d=-d;
47     }
48     if(d==0){
49         cout<<"分母不能为0。";
50     }
51     else if(u==0)
52         cout<<"0";
53     else if(d==1)
54         cout<<u;
55     else
56         cout<<u<<"/"<<d;
57 }
58 
59 Fraction add(const Fraction f1,const Fraction f2){
60     Fraction f(0,0);
61     f.down=f1.down*f2.down;
62     f.up=f1.up*f2.down+f2.up*f1.down;
63     return f;
64 }
65 
66 Fraction sub(const Fraction f1,const Fraction f2){
67     Fraction f(0,0);
68     f.down=f1.down*f2.down;
69     f.up=f1.up*f2.down-f2.up*f1.down;
70     return f;
71 }
72 
73 Fraction mul(const Fraction f1,const Fraction f2){
74     Fraction f(0,0);
75     f.up=f1.up*f2.up;
76     f.down=f1.down*f2.down;
77     return f;
78 }
79 
80 Fraction div(const Fraction f1,const Fraction f2){
81     Fraction f(0,0);
82     f.up=f1.up*f2.down;
83     f.down=f1.down*f2.up;
84     return f;
85 }
View Code

task 4.cpp

 1 #include "Fraction.h"
 2 #include <iostream>
 3 
 4 using std::cout;
 5 using std::endl;
 6 
 7 void test1() {
 8     cout << "Fraction类测试: " << endl;
 9     cout << Fraction::doc << endl << endl;
10     
11     Fraction f1(5);
12     Fraction f2(3, -4), f3(-18, 12);
13     Fraction f4(f3);
14     cout << "f1 = "; output(f1); cout << endl;
15     cout << "f2 = "; output(f2); cout << endl;
16     cout << "f3 = "; output(f3); cout << endl;
17     cout << "f4 = "; output(f4); cout << endl;
18 
19     Fraction f5(f4.negative());
20     cout << "f5 = "; output(f5); cout << endl;
21     cout << "f5.get_up() = " << f5.get_up() << ", f5.get_down() = " << f5.get_down() << endl;
22 
23     cout << "f1 + f2 = "; output(add(f1, f2)); cout << endl;
24     cout << "f1 - f2 = "; output(sub(f1, f2)); cout << endl;
25     cout << "f1 * f2 = "; output(mul(f1, f2)); cout << endl;
26     cout << "f1 / f2 = "; output(div(f1, f2)); cout << endl;
27     cout << "f4 + f5 = "; output(add(f4, f5)); cout << endl;
28 }
29 
30 void test2() {
31     Fraction f6(42, 55), f7(0, 3);
32     cout << "f6 = "; output(f6); cout << endl;
33     cout << "f7 = "; output(f7); cout << endl;
34     cout << "f6 / f7 = "; output(div(f6, f7)); cout << endl;
35 }
36 
37 int main() {
38     cout << "测试1：Fraction类基础功能测试\n";
39     test1();
40 
41     cout << "\n测试2：分母为0测试: \n";
42     test2();
43 }
View Code

 

任务五：

account.h

 1 #include<iostream>
 2 
 3 class SavingsAccount{
 4 private:
 5     int id;
 6     double balance;
 7     double rate;
 8     int lastDate;
 9     double accumulation;
10     static double total;
11     
12     void record(int date,double amount);
13     double accumulate(int date) const{
14         return accumulation+balance*(date-lastDate);
15     }
16 
17 public:
18     SavingsAccount(int date,int id,double rate);
19     int getId() const {return id;}
20     double getBalance() const{return balance;}
21     double getRate() const{return rate;}
22     static double getTotal(){return total;}
23     void deposit(int rate,double amount);
24     void withdraw(int rate,double amount);
25     void settle(int date);
26     void show() const;
27     
28 };
View Code

account.cpp

 1 #include "account.h"
 2 #include<cmath>
 3 #include<iostream>
 4 
 5 using std::cout;
 6 using std::endl;
 7 
 8 double SavingsAccount::total=0;
 9 
10 SavingsAccount::SavingsAccount(int date,int id,double rate)
11     :id(id),balance{0},rate{rate},lastDate{date},accumulation{0}{
12     cout<<date<<"\t#"<<id<<"is created"<<endl;    
13 }
14 
15 void SavingsAccount::record(int date,double amount){
16     accumulation=accumulate(date);
17     lastDate=date;
18     amount=floor(amount*100+0.5)/100;
19     balance+=amount;
20     total+=amount;
21     cout<<date<<"\t#"<<id<<"\t"<<amount<<"\t"<<balance<<endl;
22 }
23 
24 void SavingsAccount::deposit(int date,double amount){
25     record(date,amount);
26 }
27 
28 void SavingsAccount::withdraw(int date,double amount){
29     if(amount>getBalance()){
30         cout<<"Erroe:not enough money"<<endl;
31     }
32     else{
33         record(date,-amount);
34     }
35 }
36 
37 void SavingsAccount::settle(int date){
38     double interest=accumulate(date)*rate/365;
39     if(interest!=0){
40         record(date,interest);
41     }
42     accumulation=0;
43 }
44 
45 void SavingsAccount::show() const{
46     cout<<"#"<<id<<"\tBalance:"<<balance;
47 }
View Code

5_11.cpp

 1 #include "account.h"
 2 #include<iostream>
 3 
 4 using namespace std;
 5 
 6 int main(){
 7     SavingsAccount sa0(1,21325302,0.015);
 8     SavingsAccount sa1(1,58320212,0.015);
 9     
10     sa0.deposit(5,5000);
11     sa1.deposit(25,10000);
12     sa0.deposit(45,5500);
13     sa1.withdraw(60,4000);
14     
15     sa0.settle(90);
16     sa1.settle(90);
17     
18     sa0.show();cout<<endl;
19     sa1.show();cout<<endl;
20     
21     cout<<"Total:"<<SavingsAccount::getTotal()<<endl;
22     
23     return 0;
24 }
View Code

 

posted @ 2024-10-24 22:54  张欣颜  阅读(13)  评论(0)  编辑  收藏  举报