任务1
源码：
1 #pragma once
2
3 #include <string>
4
5 // 类T: 声明
6 class T {
7 // 对象属性、方法
8 public:
9 T(int x = 0, int y = 0); // 普通构造函数
10 T(const T &t); // 复制构造函数
11 T(T &&t); // 移动构造函数
12 ~T(); // 析构函数
13
14 void adjust(int ratio); // 按系数成倍调整数据
15 void display() const; // 以(m1, m2)形式显示T类对象信息
16
17 private:
18 int m1, m2;
19
20 // 类属性、方法
21 public:
22 static int get_cnt(); // 显示当前T类对象总数
23
24 public:
25 static const std::string doc; // 类T的描述信息
26 static const int max_cnt; // 类T对象上限
27
28 private:
29 static int cnt; // 当前T类对象数目
30
31 // 类T友元函数声明
32 friend void func();
33 };
34
35 // 普通函数声明
36 void func();
// 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;
}
1 #include "t.h"
2 #include <iostream>
3
4 using std::cout;
5 using std::endl;
6
7 void test();
8
9 int main() {
10 test();
11 cout << "\nmain: \n";
12 cout << "T objects'current count: " << T::get_cnt() << endl;
13 }
14
15 void test() {
16 cout << "test class T: \n";
17 cout << "T info: " << T::doc << endl;
18 cout << "T objects'max count: " << T::max_cnt << endl;
19 cout << "T objects'current count: " << T::get_cnt() << endl << endl;
20
21
22 T t1;
23 cout << "t1 = "; t1.display(); cout << endl;
24
25 T t2(3, 4);
26 cout << "t2 = "; t2.display(); cout << endl;
27
28 T t3(t2);
29 t3.adjust(2);
30 cout << "t3 = "; t3.display(); cout << endl;
31
32 T t4(std::move(t2));
33 cout << "t3 = "; t4.display(); cout << endl;
34
35 cout << "T objects'current count: " << T::get_cnt() << endl;
36
37 func();
38 }
结果：
问：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
在类内部的声明不会提醒main函数普通函数func的存在。
问：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：通过数值创建对象实例。
复制构造函数：利用一个已知的对象实例给新实例赋值。
移动构造函数：在处理临时对象是时提高效率。
析构函数：释放实例占用的内存。
问：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：不能。
任务2
源码：
1 //.h:
2 #pragma once
3
4 #include<iostream>
5 #include<cmath>
6
7 using std::cout;
8 using std::endl;
9 using std::boolalpha;
10
11 void test();
12
13 class Complex {
14 private:
15 double real, imag;
16 public:
17 static std::string doc;
18 Complex(double r = 0, double i = 0) :real{ r }, imag{ i } {}
19 Complex(const Complex& c) :real{ c.get_real() }, imag{ c.get_imag() } {}
20 double get_real() const {
21 return real;
22 }
23 double get_imag() const {
24 return imag;
25 }
26 void add(const Complex c) {
27 real += c.get_real();
28 imag += c.get_imag();
29 }
30 friend Complex add(const Complex c1, const Complex c2);
31 friend bool is_equal(const Complex& c1, const Complex& c2);
32 friend bool is_not_equal(const Complex& c1, const Complex& c2);
33 friend void output(const Complex& c);
34 friend double abs(const Complex& c);
35 };
36
37 Complex add(const Complex c1, const Complex c2);
38 bool is_equal(const Complex& c1, const Complex& c2);
39 bool is_not_equal(const Complex& c1, const Complex& c2);
40 void output(const Complex& c);
41 double abs(const Complex& c);
42
43 //.cpp:
44 #include"Complex.h"
45
46 std::string Complex::doc = "a simple complex class";
47
48 void test() {
49 cout << "类成员测试: " << endl;
50 cout << Complex::doc << endl;
51
52 cout << endl;
53
54 cout << "Complex对象测试: " << endl;
55 Complex c1;
56 Complex c2(3, -4);
57 const Complex c3(3.5);
58 Complex c4(c3);
59
60 cout << "c1 = "; output(c1); cout << endl;
61 cout << "c2 = "; output(c2); cout << endl;
62 cout << "c3 = "; output(c3); cout << endl;
63 cout << "c4 = "; output(c4); cout << endl;
64 cout << "c4.real = " << c4.get_real() << ", c4.imag = " << c4.get_imag() << endl;
65
66 cout << endl;
67
68 cout << "复数运算测试: " << endl;
69 cout << "abs(c2) = " << abs(c2) << endl;
70 c1.add(c2);
71 cout << "c1 += c2, c1 = "; output(c1); cout << endl;
72 cout << boolalpha;
73 cout << "c1 == c2 : " << is_equal(c1, c2) << endl;
74 cout << "c1 != c3 : " << is_not_equal(c1, c3) << endl;
75 c4 = add(c2, c3);
76 cout << "c4 = c2 + c3, c4 = "; output(c4); cout << endl;
77 }
78 Complex add(const Complex c1,const Complex c2) {
79 Complex c3;
80 c3.add(c2);
81 c3.add(c1);
82 return c3;
83 }
84 bool is_equal(const Complex& c1, const Complex& c2) {
85 if (c1.get_imag() == c2.get_imag() && c1.get_real() == c2.get_real())
86 {
87 return true;
88 }
89 else
90 {
91 return false;
92 }
93 }
94
95 bool is_not_equal(const Complex& c1, const Complex& c2) {
96 if (c1.get_imag() == c2.get_imag() && c1.get_real() == c2.get_real())
97 {
98 return false;
99 }
100 else
101 {
102 return true;
103 }
104 }
105
106 void output(const Complex& c) {
107 if (c.get_imag() >= 0) {
108 cout << c.get_real() << '+' << c.get_imag() << 'i' << endl;
109 }
110 else {
111 cout << c.get_real() << '-' << abs(c.get_imag()) << 'i' << endl;
112 }
113 }
114 double abs(const Complex& c) {
115 return sqrt(c.get_imag() * c.get_imag() + c.get_real() * c.get_real());
116
117 }
118
119 //.main:
120 #include"Complex.h"
121 int main() {
122 test();
123 }
结果：
任务3
源码：
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comple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 }
结果：
任务4
源码：
1 //.h
2 #pragma once
3 #include <iostream>
4
5 using std::cout;
6 using std::endl;
7
8 int measure(int x, int y);
9 class Fraction {
10 private:
11 int up;
12 int down;
13 public:
14 static std::string doc;
15 Fraction(int u, int d = 1){
16 int mea = measure(u, d);
17 up = u / mea;
18 down = d / mea;
19 if (down < 0)
20 {
21 down = -down;
22 up = -up;
23 }
24 }
25 int get_up() const {
26 return up;
27 }
28 int get_down() const {
29 return down;
30 }
31 Fraction negative() {
32 Fraction f(-up, down);
33 return f;
34 }
35 friend void output(const Fraction& f);
36 friend Fraction add(const Fraction f1, const Fraction f2);
37 friend Fraction sub(const Fraction f1, const Fraction f2);
38 friend Fraction mul(const Fraction f1, const Fraction f2);
39 friend Fraction div(const Fraction f1, const Fraction f2);
40 };
41
42 Fraction add(const Fraction f1, const Fraction f2);
43 Fraction sub(const Fraction f1, const Fraction f2);
44 Fraction mul(const Fraction f1, const Fraction f2);
45 Fraction div(const Fraction f1, const Fraction f2);
46 void output(const Fraction& f);
47
48 //.cpp
49 #include "Fraction.h"
50
51 std::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";
52 Fraction add(const Fraction f1, const Fraction f2) {
53 int up1, up2, down1, down2, up, down;
54 up1 = f1.up;
55 up2 = f2.up;
56 down1 = f1.down;
57 down2 = f2.down;
58 up = up1 * down2 + up2 * down1;
59 down = down1 + down2;
60 int mea = measure(up, down);
61 Fraction f(up / mea, down / mea);
62 return f;
63 }
64 Fraction sub(const Fraction f1, const Fraction f2) {
65 int up1, up2, down1, down2, up, down;
66 up1 = f1.up;
67 up2 = f2.up;
68 down1 = f1.down;
69 down2 = f2.down;
70 up = up1 * down2 - up2 * down1;
71 down = down1 + down2;
72 int mea = measure(up, down);
73 Fraction f(up / mea, down / mea);
74 return f;
75 }
76 Fraction mul(const Fraction f1, const Fraction f2) {
77 int up1, up2, down1, down2, up, down;
78 up1 = f1.up;
79 up2 = f2.up;
80 down1 = f1.down;
81 down2 = f2.down;
82 up = up1 * up2;
83 down = down1 * down2;
84 int mea = measure(up, down);
85 Fraction f(up / mea, down / mea);
86 return f;
87 }
88 Fraction div(const Fraction f1, const Fraction f2) {
89 if (f2.up == 0)
90 {
91 Fraction error(0, 0);
92 return error;
93 }
94 int up1, up2, down1, down2, up, down;
95 up1 = f1.up;
96 up2 = f2.up;
97 down1 = f1.down;
98 down2 = f2.down;
99 up = up1 * down2;
100 down = up2 * down1;
101 int mea = measure(up, down);
102 Fraction f(up / mea, down / mea);
103 return f;
104 }
105 void output(const Fraction& f) {
106 if (f.down != 0)
107 {
108 if (f.up == 0 || f.down == 1)
109 {
110 cout << f.up;
111 }
112 else
113 {
114 cout << f.up << "/" << f.down;
115 }
116 }
117 else
118 {
119 cout << "分母不能为0";
120 }
121 }
122 int measure(int x, int y)
123 {
124 if (y == 0)
125 {
126 return 1;
127 }
128 int z = y;
129 while (x % y != 0)
130 {
131 z = x % y;
132 x = y;
133 y = z;
134 }
135 return z;
136 }
137
138 //.main
139 #include"Fraction.h"
140
141 void test1() {
142 cout << "Fraction类测试: " << endl;
143 cout << Fraction::doc << endl << endl;
144
145 Fraction f1(5);
146 Fraction f2(3, -4), f3(-18, 12);
147 Fraction f4(f3);
148 cout << "f1 = "; output(f1); cout << endl;
149 cout << "f2 = "; output(f2); cout << endl;
150 cout << "f3 = "; output(f3); cout << endl;
151 cout << "f4 = "; output(f4); cout << endl;
152
153 Fraction f5(f4.negative());
154 cout << "f5 = "; output(f5); cout << endl;
155 cout << "f5.get_up() = " << f5.get_up() << ", f5.get_down() = " << f5.get_down() << endl;
156
157 cout << "f1 + f2 = "; output(add(f1, f2)); cout << endl;
158 cout << "f1 - f2 = "; output(sub(f1, f2)); cout << endl;
159 cout << "f1 * f2 = "; output(mul(f1, f2)); cout << endl;
160 cout << "f1 / f2 = "; output(div(f1, f2)); cout << endl;
161 cout << "f4 + f5 = "; output(add(f4, f5)); cout << endl;
162 }
163
164 void test2() {
165 Fraction f6(42, 55), f7(0, 3);
166 cout << "f6 = "; output(f6); cout << endl;
167 cout << "f7 = "; output(f7); cout << endl;
168 cout << "f6 / f7 = "; output(div(f6, f7)); cout << endl;
169 }
170
171 int main() {
172 cout << "测试1: Fraction类基础功能测试\n";
173 test1();
174
175 cout << "\n测试2: 分母为0测试: \n";
176 test2();
177 }
结果：
任务5
源码：
1 //.h
2 #ifndef __ACCOUNT_H__
3 #define __ACCOUNT_H__
4 class SavingsAccount {
5 private:
6 int id;
7 double balance;
8 double rate;
9 int lastDate;
10 double accumulation;
11 static double total;
12 void record(int date, double amount);
13 double accumulate(int date)const {
14 return accumulation + balance * (date - lastDate);
15 }
16 public:
17 SavingsAccount(int date, int id, double rate);
18 int getId()const { return id; }
19 double getBalance()const { return balance; }
20 double getRate()const { return rate; }
21 static double getTotal() { return total; }
22 void deposit(int date, double amount);
23 void withdraw(int date, double amount);
24 void settle(int date);
25 void show()const;
26 };
27 #endif // !__ACCOUNT__
28
29 //.cpp
30 #include"account.h"
31 #include<cmath>
32 #include<iostream>
33 using namespace std;
34 double SavingsAccount::total = 0;
35 SavingsAccount::SavingsAccount(int date, int id, double rate)
36 :id(id), balance(0), rate(rate), lastDate(date), accumulation(0) {
37 cout << date << "\t#" << id << " is created" << endl;
38 }
39 void SavingsAccount::record(int date, double amount) {
40 accumulation = accumulate(date);
41 lastDate = date;
42 amount = floor(amount * 100 + 0.5) / 100;
43 balance += amount;
44 total += amount;
45 cout << date << "\t#" << id << "\t" << amount << "\t" << balance << endl;
46 }
47 void SavingsAccount::deposit(int date, double amount) {
48 record(date, amount);
49 }
50 void SavingsAccount::withdraw(int date, double amount) {
51 if (amount > getBalance())
52 cout << "Error:not enough money" << endl;
53 else
54 record(date, -amount);
55 }
56 void SavingsAccount::settle(int date) {
57 double interest = accumulate(date) * rate / 365;
58 if (interest != 0)
59 record(date, interest);
60 accumulation = 0;
61 }
62 void SavingsAccount::show() const {
63 cout << "#" << id << "\tBalance:" << balance;
64 }
65
66 //.main
67 #include"account.h"
68 #include<iostream>
69 using namespace std;
70 int main() {
71 SavingsAccount sa0(1, 2132502, 0.015);
72 SavingsAccount sa1(1, 58320212, 0.015);
73 sa0.deposit(5, 5000);
74 sa1.deposit(25, 10000);
75 sa0.deposit(45, 5500);
76 sa1.withdraw(60, 4000);
77 sa0.settle(90);
78 sa1.settle(90);
79 sa0.show(); cout << endl;
80 sa1.show(); cout << endl;
81 cout << "Total:" << SavingsAccount::getTotal() << endl;
82 return 0;
83 }
结果：
标签：const,int,up,down,Complex,实验,OOP,Fraction From： https://www.cnblogs.com/syf0824/p/18503352