实验四C++

实验任务二

源代码

GradeCalc.hpp

  1 #include <iostream>
  2 #include <vector>
  3 #include <string>
  4 #include <algorithm>
  5 #include <numeric>
  6 #include <iomanip>
  7 
  8 using std::vector;
  9 using std::string;
 10 using std::cin;
 11 using std::cout;
 12 using std::endl;
 13 
 14 class GradeCalc : public vector<int> {
 15 public:
 16     GradeCalc(const string& cname, int size);
 17     void input();                             // 录入成绩
 18     void output() const;                      // 输出成绩
 19     void sort(bool ascending = false);        // 排序 (默认降序)
 20     int min() const;                          // 返回最低分
 21     int max() const;                          // 返回最高分
 22     float average() const;                    // 返回平均分
 23     void info();                              // 输出课程成绩信息 
 24 
 25 private:
 26     void compute();     // 成绩统计
 27 
 28 private:
 29     string course_name;     // 课程名
 30     int n;                  // 课程人数
 31     vector<int> counts = vector<int>(5, 0);      // 保存各分数段人数（[0, 60), [60, 70), [70, 80), [80, 90), [90, 100]
 32     vector<double> rates = vector<double>(5, 0); // 保存各分数段比例 
 33 };
 34 
 35 GradeCalc::GradeCalc(const string& cname, int size) : course_name{ cname }, n{ size } {}
 36 
 37 void GradeCalc::input() {
 38     int grade;
 39 
 40     for (int i = 0; i < n; ++i) {
 41         cin >> grade;
 42         this->push_back(grade);
 43     }
 44 }
 45 
 46 void GradeCalc::output() const {
 47     for (auto ptr = this->begin(); ptr != this->end(); ++ptr)
 48         cout << *ptr << " ";
 49     cout << endl;
 50 }
 51 
 52 void GradeCalc::sort(bool ascending) {
 53     if (ascending)
 54         std::sort(this->begin(), this->end());
 55     else
 56         std::sort(this->begin(), this->end(), std::greater<int>());
 57 }
 58 
 59 int GradeCalc::min() const {
 60     return *std::min_element(this->begin(), this->end());
 61 }
 62 
 63 int GradeCalc::max() const {
 64     return *std::max_element(this->begin(), this->end());
 65 }
 66 
 67 float GradeCalc::average() const {
 68     return std::accumulate(this->begin(), this->end(), 0) * 1.0 / n;
 69 }
 70 
 71 void GradeCalc::compute() {
 72     for (int grade : *this) {
 73         if (grade < 60)
 74             counts.at(0)++;
 75         else if (grade >= 60 && grade < 70)
 76             counts.at(1)++;
 77         else if (grade >= 70 && grade < 80)
 78             counts.at(2)++;
 79         else if (grade >= 80 && grade < 90)
 80             counts.at(3)++;
 81         else if (grade >= 90)
 82             counts.at(4)++;
 83     }
 84 
 85     for (int i = 0; i < rates.size(); ++i)
 86         rates.at(i) = counts.at(i) * 1.0 / n;
 87 }
 88 
 89 void GradeCalc::info() {
 90     cout << "课程名称:\t" << course_name << endl;
 91     cout << "排序后成绩: \t";
 92     sort();  output();
 93     cout << "最高分:\t" << max() << endl;
 94     cout << "最低分:\t" << min() << endl;
 95     cout << "平均分:\t" << std::fixed << std::setprecision(2) << average() << endl;
 96 
 97     compute();  // 统计各分数段人数、比例
 98 
 99     vector<string> tmp{ "[0, 60)  ", "[60, 70)", "[70, 80)","[80, 90)", "[90, 100]" };
100     for (int i = tmp.size() - 1; i >= 0; --i)
101         cout << tmp[i] << "\t: " << counts[i] << "人\t"
102         << std::fixed << std::setprecision(2) << rates[i] * 100 << "%" << endl;
103 }

demo2.cpp

 1 #include "GradeCalc.hpp"
 2 #include <iomanip>
 3 
 4 void test() {
 5     int n;
 6     cout << "输入班级人数: ";
 7     cin >> n;
 8 
 9     GradeCalc c1("OOP", n);
10 
11     cout << "录入成绩: " << endl;;
12     c1.input();
13     cout << "输出成绩: " << endl;
14     c1.output();
15 
16     cout << string(20, '*') + "课程成绩信息" + string(20, '*') << endl;
17     c1.info();
18 }
19 
20 int main() {
21     test();
22 }

运行结果截图

问题1.贮存在this指针指向的地方，继承的vector的at接口，使用的vector的push_back接口。

问题2.用于计算成绩的累加和，有影响，乘1.0可以将数据转变为double类型

问题3.还可以增加后续数据有改动的情况。

实验任务三

源代码

GradeCalc.hpp

  1 #include <iostream>
  2 #include <vector>
  3 #include <string>
  4 #include <algorithm>
  5 #include <numeric>
  6 #include <iomanip>
  7 
  8 using std::vector;
  9 using std::string;
 10 using std::cin;
 11 using std::cout;
 12 using std::endl;
 13 
 14 class GradeCalc {
 15 public:
 16     GradeCalc(const string& cname, int size);
 17     void input();                             // 录入成绩
 18     void output() const;                      // 输出成绩
 19     void sort(bool ascending = false);        // 排序 (默认降序)
 20     int min() const;                          // 返回最低分
 21     int max() const;                          // 返回最高分
 22     float average() const;                    // 返回平均分
 23     void info();                              // 输出课程成绩信息 
 24 
 25 private:
 26     void compute();     // 成绩统计
 27 
 28 private:
 29     string course_name;     // 课程名
 30     int n;                  // 课程人数
 31     vector<int> grades;     // 课程成绩
 32     vector<int> counts = vector<int>(5, 0);      // 保存各分数段人数（[0, 60), [60, 70), [70, 80), [80, 90), [90, 100]
 33     vector<double> rates = vector<double>(5, 0); // 保存各分数段比例 
 34 };
 35 
 36 GradeCalc::GradeCalc(const string& cname, int size) : course_name{ cname }, n{ size } {}
 37 
 38 void GradeCalc::input() {
 39     int grade;
 40 
 41     for (int i = 0; i < n; ++i) {
 42         cin >> grade;
 43         grades.push_back(grade);
 44     }
 45 }
 46 
 47 void GradeCalc::output() const {
 48     for (int grade : grades)
 49         cout << grade << " ";
 50     cout << endl;
 51 }
 52 
 53 void GradeCalc::sort(bool ascending) {
 54     if (ascending)
 55         std::sort(grades.begin(), grades.end());
 56     else
 57         std::sort(grades.begin(), grades.end(), std::greater<int>());
 58 
 59 }
 60 
 61 int GradeCalc::min() const {
 62     return *std::min_element(grades.begin(), grades.end());
 63 }
 64 
 65 int GradeCalc::max() const {
 66     return *std::max_element(grades.begin(), grades.end());
 67 }
 68 
 69 float GradeCalc::average() const {
 70     return std::accumulate(grades.begin(), grades.end(), 0) * 1.0 / n;
 71 }
 72 
 73 void GradeCalc::compute() {
 74     for (int grade : grades) {
 75         if (grade < 60)
 76             counts.at(0)++;
 77         else if (grade >= 60 && grade < 70)
 78             counts.at(1)++;
 79         else if (grade >= 70 && grade < 80)
 80             counts.at(2)++;
 81         else if (grade >= 80 && grade < 90)
 82             counts.at(3)++;
 83         else if (grade >= 90)
 84             counts.at(4)++;
 85     }
 86 
 87     for (int i = 0; i < rates.size(); ++i)
 88         rates.at(i) = counts.at(i) * 1.0 / n;
 89 }
 90 
 91 void GradeCalc::info() {
 92     cout << "课程名称:\t" << course_name << endl;
 93     cout << "排序后成绩: \t";
 94     sort();  output();
 95     cout << "最高分:\t" << max() << endl;
 96     cout << "最低分:\t" << min() << endl;
 97     cout << "平均分:\t" << std::fixed << std::setprecision(2) << average() << endl;
 98 
 99     compute();  // 统计各分数段人数、比例
100 
101     vector<string> tmp{ "[0, 60)  ", "[60, 70)", "[70, 80)","[80, 90)", "[90, 100]" };
102     for (int i = tmp.size() - 1; i >= 0; --i)
103         cout << tmp[i] << "\t: " << counts[i] << "人\t"
104         << std::fixed << std::setprecision(2) << rates[i] * 100 << "%" << endl;
105 }

demo.cpp

 1 #include "GradeCalc.hpp"
 2 #include <iomanip>
 3 
 4 void test() {
 5     int n;
 6     cout << "输入班级人数: ";
 7     cin >> n;
 8 
 9     GradeCalc c1("OOP", n);
10 
11     cout << "录入成绩: " << endl;;
12     c1.input();
13     cout << "输出成绩: " << endl;
14     c1.output();
15 
16     cout << string(20, '*') + "课程成绩信息" + string(20, '*') << endl;
17     c1.info();
18 }
19 
20 int main() {
21     test();
22 }

运行结果截图

问题1.成绩存在grades这个vector类型的对象中，是通过grades调用的vector中的at接口

问题2.面向对象设计时，可以继承设计派生类，也可以设计对象类型来运用

实验任务四

4.1

源代码

 1 #include <iostream>
 2 #include <string>
 3 #include <limits>
 4 
 5 using namespace std;
 6 
 7 void test1() {
 8     string s1, s2;
 9     cin >> s1 >> s2;  // cin: 从输入流读取字符串, 碰到空白符(空格/回车/Tab)即结束
10     cout << "s1: " << s1 << endl;
11     cout << "s2: " << s2 << endl;
12 }
13 
14 void test2() {
15     string s1, s2;
16     getline(cin, s1);  // getline(): 从输入流中提取字符串，直到遇到换行符
17     getline(cin, s2);
18     cout << "s1: " << s1 << endl;
19     cout << "s2: " << s2 << endl;
20 }
21 
22 void test3() {
23     string s1, s2;
24     getline(cin, s1, ' '); //从输入流中提取字符串，直到遇到指定分隔符
25     getline(cin, s2);
26     cout << "s1: " << s1 << endl;
27     cout << "s2: " << s2 << endl;
28 }
29 
30 int main() {
31     cout << "测试1: 使用标准输入流对象cin输入字符串" << endl;
32     test1();
33     cout << endl;
34 
35     cin.ignore(numeric_limits<streamsize>::max(), '\n');
36 
37     cout << "测试2: 使用函数getline()输入字符串" << endl;
38     test2();
39     cout << endl;
40 
41     cout << "测试3: 使用函数getline()输入字符串, 指定字符串分隔符" << endl;
42     test3();
43 }

运行结果截图

问题1.去掉后，测试2中的s1会变成空串，作用是清空输入缓冲区，直到遇到换行符为止

4.2

源代码

 1 #include <iostream>
 2 #include <string>
 3 #include <vector>
 4 #include <limits>
 5 
 6 using namespace std;
 7 
 8 void output(const vector<string>& v) {
 9     for (auto& s : v)
10         cout << s << endl;
11 }
12 
13 void test() {
14     int n;
15     while (cout << "Enter n: ", cin >> n) {
16         vector<string> v1;
17 
18         for (int i = 0; i < n; ++i) {
19             string s;
20             cin >> s;
21             v1.push_back(s);
22         }
23 
24         cout << "output v1: " << endl;
25         output(v1);
26         cout << endl;
27     }
28 }
29 
30 int main() {
31     cout << "测试: 使用cin多组输入字符串" << endl;
32     test();
33 }

运行结果截图

4.3

源代码

 1 #include <iostream>
 2 #include <string>
 3 #include <vector>
 4 #include <limits>
 5 
 6 using namespace std;
 7 
 8 void output(const vector<string>& v) {
 9     for (auto& s : v)
10         cout << s << endl;
11 }
12 
13 void test() {
14     int n;
15     while (cout << "Enter n: ", cin >> n) {
16         cin.ignore(numeric_limits<streamsize>::max(), '\n');
17 
18         vector<string> v2;
19 
20         for (int i = 0; i < n; ++i) {
21             string s;
22             getline(cin, s);
23             v2.push_back(s);
24         }
25         cout << "output v2: " << endl;
26         output(v2);
27         cout << endl;
28     }
29 }
30 
31 int main() {
32     cout << "测试: 使用函数getline()多组输入字符串" << endl;
33     test();
34 }

运行结果截图

问题1.清空输入缓冲区

实验任务五

源代码

grm.hpp

 1 template<typename T>
 2 class GameResourceManager {
 3 private:
 4     T resource;
 5 public:
 6     GameResourceManager(T R);
 7     T get()const;
 8     void update(T newR);
 9 };
10 
11 
12 
13 template<typename T>
14 GameResourceManager<T>::GameResourceManager(T R) :resource{ R } {}
15 template<typename T>
16 T GameResourceManager<T>::get()const { return resource; }
17 template<typename T>
18 void GameResourceManager<T>::update(T newR) {
19     resource += newR;
20     if (resource < 0)
21         resource = 0;
22 }

task5.cpp

 1 #include "grm.hpp"
 2 #include <iostream>
 3 
 4 using std::cout;
 5 using std::endl;
 6 
 7 void test1() {
 8     GameResourceManager<float> HP_manager(99.99);
 9     cout << "当前生命值: " << HP_manager.get() << endl;
10     HP_manager.update(9.99);
11     cout << "增加9.99生命值后, 当前生命值: " << HP_manager.get() << endl;
12     HP_manager.update(-999.99);
13     cout << "减少999.99生命值后, 当前生命值: " << HP_manager.get() << endl;
14 }
15 
16 void test2() {
17     GameResourceManager<int> Gold_manager(100);
18     cout << "当前金币数量: " << Gold_manager.get() << endl;
19     Gold_manager.update(50);
20     cout << "增加50个金币后, 当前金币数量: " << Gold_manager.get() << endl;
21     Gold_manager.update(-99);
22     cout << "减少99个金币后, 当前金币数量: " << Gold_manager.get() << endl;
23 }
24 
25 
26 int main() {
27     cout << "测试1: 用float类型对类模板GameResourceManager实例化" << endl;
28     test1();
29     cout << endl;
30 
31     cout << "测试2: 用int类型对类模板GameResourceManager实例化" << endl;
32     test2();
33 }

运行结果截图

实验任务六

源代码

 info.hpp

 1 #include<iostream>
 2 #include<string>
 3 #include<iomanip>
 4 
 5 using std::string;
 6 using std::cout;
 7 using std::endl;
 8 
 9 
10 class Info{
11 private:
12     string nickname;
13     string contact;
14     string city;
15     int n;
16 
17 public:
18     Info(string N,string C,string Ci,int n0):nickname{N},contact{C},city{Ci},n{n0}{}
19     void display() {
20         cout << "昵称：\t\t" << nickname<<endl;
21         cout << "联系方式：\t" << contact<<endl;
22         cout << "所在城市：\t" << city<<endl;
23         cout << "预定人数：\t" << n << endl;
24     }
25 };

task6.cpp

 1 #include"info.hpp"
 2 #include<iostream>
 3 #include<vector>
 4 using namespace std;
 5 int main() {
 6     const int capacity = 100;
 7     vector<Info> audience_lst;
 8     string name, contact, city;
 9     int n,num=0;
10     cout << "录入用户预约信息" << endl;
11     cout << endl;
12     cout << "昵称\t" << "联系方式（邮箱/手机号）\t" << "所在城市\t" << "预定参加人数\t"<<endl;
13     while (cin>>name>>contact>>city>>n) {
14         Info s(name, contact, city, n);
15         num += n;
16         if (num > capacity)
17         {
18             num -= n;
19             char ch;
20             cout << "对不起，只剩" << capacity-num << "个位置" << endl;
21             cout << "1.输入u,更新（update）预定信息" << endl;
22             cout << "2.输入q，退出预定" << endl;
23             cout << "你的选择：";
24             cin >> ch;
25             if (ch == 'u') {
26                 cout << "请重新输入预定信息" << endl;
27                 continue;
28             }
29             else if (ch == 'q')
30                 break;
31 
32 
33         }
34         else if (num == capacity) {
35             audience_lst.push_back(s);
36             break;
37         }
38         else
39             audience_lst.push_back(s);
40     }
41     cout << "截至目前一共有" << num << "位听众预约，预约听众信息如下：" << endl;
42         
43     for (auto i : audience_lst) {
44 
45         cout<< string(20, '-') << endl;
46         i.display();
47     }
48         
49 
50 
51 
52     
53 }

运行结果截图

实验任务7

源代码

date.h

 1 #pragma once
 2 
 3 class Date {
 4 private:
 5     int year;
 6     int month;
 7     int day;
 8     int totalDays;
 9 public:
10     Date(int year, int maonth, int day);
11     int getYear()const { return year; }
12     int getMonth()const { return month; }
13     int getDay()const { return day; }
14     int getMaxDay()const;
15     bool isLeapYear()const {
16         return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
17     }
18     void show()const;
19     int diatance(const Date& date)const {
20         return totalDays - date.totalDays;
21     }
22 };

date.cpp

 1 #include"date.h"
 2 #include<iostream>
 3 #include<cstdlib>
 4 using namespace std;
 5 namespace {
 6     const int DATS_BEFORE_MONTH[] = { 0,31,59,90,120,151,181,212,243,273,304,334,365 };
 7 }
 8 
 9 Date::Date(int year, int month, int day) :year{ year }, month{ month }, day{ day } {
10     if (day <= 0 || day > getMaxDay()) {
11         cout << "Invalid date: ";
12         show();
13         exit(1);
14     }
15     int years = year - 1;
16     totalDays = years * 365 + years / 4 - years / 100 + years / 400 + DATS_BEFORE_MONTH[month - 1] + day;
17     if (isLeapYear() && month > 2)totalDays++;
18 }
19 
20 int Date::getMaxDay()const {
21     if (isLeapYear() && month == 2)
22         return 29;
23     else
24         return DATS_BEFORE_MONTH[month] - DATS_BEFORE_MONTH[month - 1];
25 }
26 
27 void Date::show()const {
28     cout << getYear() << "-" << getMonth() << "-" << getDay();
29 }

accumulator.h

 1 #pragma once
 2 #include"date.h"
 3 class Accumulator {
 4 private:
 5     Date lastDate;
 6     double value;
 7     double sum;
 8 public:
 9     Accumulator(const Date &date,double value):
10         lastDate(date),value(value),sum(0){}
11     double getSum(const Date& date)const {
12         return sum + value * date.diatance(lastDate);
13     }
14     void change(const Date& date, double value) {
15         sum = getSum(date);
16         lastDate = date;
17         this->value = value;
18     }
19     void reset(const Date& date, double value) {
20         lastDate = date;
21         this->value = value;
22         sum = 0;
23     }
24 };

account.h

 1 #pragma once
 2 
 3 #include"date.h"
 4 #include"accumulator.h"
 5 #include<string>
 6 
 7 class Account {
 8 private:
 9     std::string id;
10     double balance;
11     static double total;
12 protected:
13     Account(const Date& date, const std::string& id);
14     void record(const Date& date, double amount, const std::string& desc);
15     void error(const std::string& msg)const;
16 
17 
18 public:
19     
20     const std::string& getId()const { return id; }
21     double getBalance()const { return balance; }
22     static double getTotal() { return total; }
23     void show()const;
24 };
25 
26 class SavingAccount :public Account {
27 private:
28     Accumulator acc;
29     double rate;
30 public:
31     SavingAccount(const Date& date, const std::string& id, double rate);
32     double getRate()const { return rate;}
33     void deposit(const Date& date, double amount, const std::string& desc);
34     void withdraw(const Date& date, double amount, const std::string& desc);
35     void settle(const Date& date);
36 };
37 class CreditAccount :public Account {
38 private:
39     Accumulator acc;
40     double credit;
41     double rate;
42     double fee;
43     double getDebt()const {
44         double balance = getBalance();
45         return (balance < 0 ? balance : 0);
46     }
47 public:
48     CreditAccount(const Date& date, const std::string& id, double credit, double rate, double fee);
49     double getCredit()const { return credit; }
50     double getRate() const { return rate; }
51     double getFee() const { return fee; }
52     double getAvsilbilableCredit() const {
53         if (getBalance() < 0)
54             return credit + getBalance();
55         else
56             return credit;
57     }
58     void deposit(const Date& date, double amount, const std::string& desc);
59     void withdraw(const Date& date, double amount, const std::string& desc);
60     void settle(const Date& date);
61     void show()const;
62 };

account.cpp

 1 #include"account.h"
 2 #include<cmath>
 3 #include<iostream>
 4 using namespace std;
 5 double Account::total = 0;
 6 
 7 Account::Account(const Date& date, const string& id) :id{ id }, balance{ 0 }{
 8     date.show();
 9     cout << "\t#" << id << "created" << endl;
10 }
11 void Account::record(const Date& date, double amount, const string& desc) {
12     amount = floor(amount * 100 + 0.5) / 100;
13     balance += amount;
14     total += amount;
15     date.show();
16     cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl;
17 }
18 void Account::show()const {
19     cout << id << "\tBalance:" << balance;
20 }
21 void Account::error(const string& msg)const {
22     cout << "Error(#" << id << "): " << msg << endl;
23 }
24 
25 SavingAccount::SavingAccount(const Date& date, const string& id, double rate) :Account{ date,id }, rate{ rate }, acc{ date,0 } {}
26 void SavingAccount::deposit(const Date& date, double amount, const string& desc) {
27     record(date, amount, desc);
28     acc.change(date, getBalance());
29 }
30 void SavingAccount::withdraw(const Date& date, double amount, const string& desc) {
31     if (amount > getBalance())
32         error("not enough money");
33     else
34         record(date, -amount, desc);
35     acc.change(date, getBalance());
36 }
37 
38 void SavingAccount::settle(const Date& date) {
39     double interest = acc.getSum(date) * rate / date.diatance(Date(date.getYear() - 1, 1, 1));
40     if (interest != 0)
41         record(date, interest, "interest");
42     acc.reset(date, getBalance());
43 
44 }
45 
46 
47 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 } {}
48 
49 void CreditAccount::deposit(const Date& date, double amount, const string& desc) {
50     record(date, amount, desc);
51     acc.change(date, getDebt());
52 }
53 void CreditAccount::withdraw(const Date& date, double amount, const string& desc) {
54     if (amount - getBalance()>credit)
55         error("not enough money");
56     else
57         record(date, -amount, desc);
58     acc.change(date, getDebt());
59 }
60 
61 void CreditAccount::settle(const Date& date) {
62     double interest = acc.getSum(date) * rate;
63     if (interest != 0)
64         record(date, interest, "interest");
65     if (date.getMonth() == 1)
66         record(date, -fee, "annual fee");
67     acc.reset(date,getDebt());
68 
69 }
70 void CreditAccount::show()const {
71     Account::show();
72     cout << "\tAvailable credit:"<<getAvsilbilableCredit();
73 }

7_10.cpp

 1 #include"account.h"
 2 #include<iostream>
 3 using namespace std;
 4 int main() {
 5     Date date(2008, 11, 1);
 6     SavingAccount sa1(date, "s3755217", 0.015);
 7     SavingAccount sa2(date, "02342342", 0.015);
 8     CreditAccount ca(date, "c5392394", 10000, 0.0005, 50);
 9 
10     sa1.deposit(Date(2008, 11, 5), 5000, "salary");
11     ca.withdraw(Date(2008, 11, 15), 2000, "buy a cell");
12     sa2.deposit(Date(2008, 11, 25), 10000, "sell stock 0323");
13 
14     ca.settle(Date(2008, 12, 1));
15 
16     ca.deposit(Date(2008, 12, 1), 2016, "repay the credit");
17     sa1.deposit(Date(2008, 12, 5), 5500, "salary");
18 
19     sa1.settle(Date(2009, 1, 1)); 
20     sa2.settle(Date(2009, 1, 1)); 
21     ca.settle(Date(2009, 1, 1));
22 
23     cout << endl;
24     sa1.show();cout << endl;
25     sa2.show();cout << endl;
26     ca.show();cout << endl;
27     cout << "Total: " << Account::getTotal() << endl;
28     return 0;
29 }

运行结果截图

 

posted @ 2024-11-25 15:27  笔墨书稠  阅读(5)  评论(0)  编辑  收藏  举报