实验4 现代C++标准库与类模板

#include <iostream>

using std::cout;
using std::endl;

class A{
public:
    A(int x0, int y0): x{ x0 }, y{ y0 } {}
    void show() const { cout << x << ", " << y << endl; }
private:
    int x, y;
};

class B{
public:
    B(double x0, double y0): x{ x0 }, y{ y0 } {}
    void show() const { cout << x << ", " << y << endl;}
private:
    double x, y;
};

void test() {
    cout << "测试类A: " << endl;
    A a(3, 4);
    a.show();

    cout << "\n测试类B: " << endl;
    B b(3.2, 5.6);
    b.show();
}

int main() {
    test();
}

#include <iostream>
#include <string>

using std::cout;
using std::endl;

template<typename T>
class X{
public:
    X(T x0, T y0): x{x0}, y{y0} {}
    void show() const { cout << x << ", " << y << endl;}
private:
    T x, y;
};

void test() {
    cout << "测试1: 模板类抽象类型T用int实例化" << endl;
    X<int> x1(3, 4);
    x1.show();

    cout << "\n测试2: 模板类抽象类型T用double实例化" << endl;
    X<double> x2(3.2, 5.6);
    x2.show();

    cout << "\n测试3: 模板类抽象类型T用标准库中的string实例化" << endl;
    X<std::string> x3("hello", "c plus plus");
    x3.show();
}

int main() {
    test();
}

#include <iostream>
#include <string>
#include <limits>

using namespace std;

int main() {
    
    const int n = 10;
    string prompt = string(n, '*') + "Enter a string: " + string(n, '*') + '\n';

    cout << "测试1:";
    cout << prompt;
    string s1;
    cin >> s1;
    cout << "s1: " << s1 << endl;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');

    cout << "\n测试2:";
    cout << prompt;
    getline(cin, s1); 
    cout << "s1: " << s1 << endl;

    cout << "\n测试3:";
    string s2, s3;
    cout << prompt;
    getline(cin, s2, ' ');
    getline(cin, s3);
    cout << "s2: " << s2 << endl;
    cout << "s3: " << s3 << endl;
}

#include <iostream>
#include <string>

int main() {
    using namespace std;

    string s;

    cout << "Enter words: \n";

    while( getline(cin, s) ) {
        for(auto &ch: s)
            ch = toupper(ch);
        cout << s << "\n";
    }
}

#include <iostream>
#include <string>
#include <algorithm>

int main() {
    using namespace std;

    string s1;

    cout << "Enter words: \n";
    getline(cin, s1);
    cout << "original words: \n";
    cout << s1 <<endl;
    cout << "to uppercase: \n";
    transform(s1.begin(), s1.end(), s1.begin(), ::toupper);
    cout << s1 << endl;
}

#include <iostream>
#include <string>

int main() {
    using namespace std;

    string s1, s2;
    s1 = "nuist";
    s1[0] = 'N';
    s1.at(1) = 'U';
    cout << boolalpha << (s1 == "nuist") << endl;
    cout << s1.length() << endl;
    cout << s1.size() << endl;
    s2 = s1 + ", 2050";
    cout << s2 << endl;

    string email{"xyz@gmail.com"};
    auto pos = email.find("@");
    if (pos == string::npos)
        cout << "illegal email address";
    else {
        auto s1 = email.substr(0, pos);
        auto s2 = email.substr(pos + 1);
        cout << s1 << endl;
        cout << s2 << endl;
    }

    string phone{"15216982937"};
    cout << phone.replace(3, 5, string(5, '*')) << endl;

    string s3{"cosmos"}, s4{"galaxy"};
    cout << "s3: " + s3 + " s4: " + s4 << endl;
    s3.swap(s4);
    cout << "s3: " + s3 + " s4: " + s4 << endl;

    string s5{"abc"};
    const char *pstr = s5.c_str();
    cout << pstr << endl;

    string s6{"12306"};
    int x1 = stoi(s6);
    cout << x1 << endl;

    int x2 = 12306;
    string s7 = to_string(x2);
    cout << s7 << endl;

    double x3 = 123.06;
    string s8 = to_string(x3);
    cout << s8 << endl;
}

#include <iostream>
#include <vector>


template<typename T>
void output(const T &obj) {
    for(auto &item: obj)
        std::cout << item << ", ";
    std::cout << "\b\b \n";
}

int main() {
    using namespace std;

    vector<int> v1;
    vector<int> v2(5);
    vector<int> v3(5, 42);
    vector<int> v4{1, 9, 8, 4};
    vector<int> v5{v4};

    cout << "v2: ";
    output(v2);

    cout << "v3: ";
    output(v3);

    cout << "v4: ";
    output(v4);

    cout << "v5: ";
    output(v5);
}

#include <iostream>
#include <vector>

using std::cout;
using std::endl;
using std::vector;

void output(const vector<int> &v) {
    cout << "v.size() = " << v.size() << endl;
    cout << "v.capacity() = " << v.capacity() << endl;
    cout << endl;
}

int main() {
    vector<int> v{42};
    output(v);

    v.push_back(55);
    v.push_back(90);
    output(v);

    for(auto i = 0; i < 8; ++i)
        v.push_back(i);
    output(v);

    v.pop_back();
    output(v);
}

#include <iostream>
#include <vector>
#include <array>
#include <string>
#include <algorithm>

using namespace std;

template<typename T>
void output1(const T &obj) {
    for(auto i = 0; i < obj.size(); ++i)
        cout << obj.at(i) << ", ";
    cout << "\b\b \n";
}

template<typename T>
void output2(const T &obj) {
    for(auto p = obj.cbegin(); p != obj.cend(); ++p)
        cout << *p << ", ";
    cout << "\b\b \n";
}

template<typename T>
void output3(const T &obj) {
    for(auto &item: obj) 
        cout << item << ", ";
    cout << "\b\b \n";
}

void test1() {
    string s1{"cplus"};

    output1(s1);

    reverse(s1.begin(), s1.end());
    output2(s1);

    sort(s1.begin(), s1.end()); 
    output3(s1);
}

void test2() {
    array< array<int, 4>, 3> x{1, 9, 8, 4, 2, 0, 2, 3, 2, 0, 4, 9 };

    output1( x.at(0) );
    output2( x.at(1) );
    output3( x.at(2) );
}

void test3() {
    vector<string> v1 {"Sheldon", "Leonard", "Howard", "Raj"};

    v1.push_back("Penny");
    v1.push_back("Amy");

    output1(v1);

    sort(v1.begin(), v1.end(), std::greater<string>());
    output2(v1);

    reverse(v1.begin(), v1.end());
    output3(v1);
}

int main() {
    cout << "测试1: " << endl;
    test1();

    cout << "测试2: " << endl;
    test2();

    cout << "测试3: " << endl;
    test3();
}

#include "textcoder.hpp"
#include <iostream>
#include <string>

void test() {
    using namespace std;

    string text, encoded_text, decoded_text;

    cout << "输入英文文本: ";
    while (getline(cin, text)) {
        encoded_text = TextCoder(text).get_ciphertext();
        cout << "加密后英文文本:\t" << encoded_text << endl;

        decoded_text = TextCoder(encoded_text).get_deciphertext();
        cout << "解密后英文文本:\t" << decoded_text << endl;
        cout << "\n输入英文文本: ";
    }
}

int main() {  
    test(); 
}

#include<iostream>
#include<string>

using std::string;

class TextCoder {
    private:
        string text;
        void encoder();
        void decoder();
    public:
        TextCoder(string &str);
        TextCoder(const TextCoder &t);
        string get_ciphertext();
        string get_deciphertext();
};
TextCoder::TextCoder(string &str):text{str} {
}
TextCoder::TextCoder(const TextCoder &t):text{t.text} {
}
void TextCoder::encoder() {
    for (auto &i : text) {
        i=i+7;
    }
}
void TextCoder::decoder() {
    for (auto &i : text) {
        i=i-7;
    }

}
string TextCoder::get_ciphertext() {
    encoder();
    return text;
}
string TextCoder::get_deciphertext() {
    decoder();
    return text;
}

#include "Info.hpp"
#include<iostream>
#include<string>
#include <vector>

using namespace std;

int main()
{
    const int capacity=100;
    vector<Info> audience_info_list;
    
    cout << "录入信息：" << endl;
    cout << endl;
    cout << "昵称     联系方式(邮箱/手机号)     所在城市     预定参加人数     " << endl;
    char choice;
    int sum=0;
    string name, contact, city;
    int n;
    while(cin >> name >> contact >> city >> n)
    {
        sum+=n;
        
        if(sum > capacity)
        {
            sum-=n;
            cout << "对不起，只剩" << capacity-sum << "个位置" << endl;
            cout << "1.输入u，更新（update）预定信息" << endl
                 << "2.输入q, 退出预定" << endl
                 <<"你的选择: ";
            cin >> choice;
            
            if(choice=='u')
            {
                cin >> name >> contact >> city >> n;
                Info a(name,contact,city,n);
                audience_info_list.push_back(a);
                sum+=n;
            }
            else 
             break;
        }
        else audience_info_list.push_back(Info(name, contact, city, n));
    }
    cout << "截至目前，一共有" << sum << "位听众预定参加。预定听众信息如下：" << endl;
    for(auto &Info:audience_info_list)
    {
        Info.print();
    }
}

#pragma once 

#include<iostream>
#include<string>
#include <iomanip>

using namespace std;
class Info{
public:
    Info(string nickname0, string contact0, string city0, int n0);
    ~Info()=default;

    void print() const;
    
private:
    string nickname,contact,city;
    int n;
};

Info::Info(string nickname0, string contact0, string city0, int n0)
{
    nickname = nickname0;
    contact = contact0;
    city = city0;
    n=n0;
}

void Info::print() const
{
    cout << "昵称:     " << nickname << endl;
    cout << "联系方式:     " << contact << endl;
    cout << "所在城市:     " << city << endl;
    cout << "预定参加人数:     " << n << endl;
}