任务五源码：

#ifndef INFO_HPP
#define INFO_HPP
#include<iostream>
#include<iomanip>
#include <string>
using namespace std;
class Info
{
public:
    Info(string n, string co, string c, string nn);
    void print();

    static int s;
    string nickname, contact, city, n;
    
};
int Info::s = 0;
Info::Info(string na, string co, string c, string nn) :nickname{ na }, contact{ co }, city{ c }, n{ nn }{s += stoi(nn); };

void Info::print()
{
    cout << setw(13) 
         <<left
         << nickname
         << setw(20)
         << contact
         << setw(13)
         << city 
         << setw(13)
         << n <<endl;

}
#endif

#include"info.hpp"
#include <iostream>
#include<vector>
#include<limits>
#define MAX 100

int main()
{
    vector<Info> audience_info_list;

    const int capacity = MAX;
    string s1, s2, s3, s4;
    std::cout << "please input nickname、contact、city and num:";
    while (1)
    {
        if (Info::s > capacity)
        {
            std::cout << "录入信息：" << endl
                << "称呼/昵称 联系方式（邮箱/手机号） 所在城市 预定参加人数" << endl;
            for (auto i = audience_info_list.begin(); i != audience_info_list.end(); i++)
                i->print();
                cout << endl << endl;
            std::cout << "对不起，只剩 " << capacity - (Info::s-stoi(s4) )<< "个位置"<<endl
                << "1、输入u更新预订信息"<<endl
                <<"2、输入q退出预订"<<endl
                <<"你的选择：";
            char c = getchar();
            auto it = audience_info_list.end() - 1;
            if (c == 'q')
            {
                it=audience_info_list.erase(it);
                Info::s -= stoi(s4);
                break;

            }
            else if (c == 'u')
            {
                it= audience_info_list.erase(it);
                Info::s -= stoi(s4);
                cout << "please input nickname、contact、city and num:";
                c = getchar();
                getline(cin, s1, ' ');

                
            }
        }
        else if (!getline(cin, s1, ' ')|| Info::s == capacity)
        {
            cout << "录入信息：" << endl
                << "称呼/昵称 联系方式（邮箱/手机号） 所在城市 预定参加人数" << endl;
            for (auto i = audience_info_list.begin(); i != audience_info_list.end(); i++)
                i->print();
            cout <<endl << endl;
            break;
        }
        
        getline(cin, s2, ' '); getline(cin, s3, ' '); getline(cin, s4);

        Info i(s1, s2, s3, s4);
        audience_info_list.push_back(i);
    }
    cout << "截至目前，一共有" << Info::s << "位听众预定参加，听众信息如下:" << endl;
    for (auto i = audience_info_list.begin(); i != audience_info_list.end(); i++)
        cout << setw(15)<< "称呼:" <<"\t"<< i->nickname << endl
             << "联系方式：" << "\t"<< i->contact << endl
             << "所在城市：" <<  "\t" << i->city << endl
             << "预定人数：" << "\t" << i->n << endl;
            
    return 0;

    }

 任务六源码：

#ifndef TEXTCODER_HPP
#define TEXTCODER_HPP
#include <iostream>
#include <string>
using namespace std;
class TextCoder
{
public:
    TextCoder(string s = " ") :text{ s } {};
    string encoder();
    string decoder();
private:
    string text;
};
string TextCoder::encoder() {
    for (auto& i : text)
        if (i >= 'A' && i <= 'U')
            i = i + 5;
        else if (i > 'U' && i <= 'Z')
            i = (i + 5 )%'Z' + 'A'-1;
        else if (i >= 'a' && i <= 'u')
            i = i + 5;
        else if (i > 'u' && i <= 'z')
            i =( i + 5 )% 'z' + 'a'-1;
        else;
        
        
    return text;

};
string TextCoder::decoder()
{
    for (auto& i : text)
        if (i >= 'A' && i <= 'E')
            i = i - 5 + 26;
        else if (i > 'E' && i <= 'Z')
            i = i - 5;
            else if (i >= 'a' && i <= 'e')
                i = i - 5+26;
            else if (i > 'e' && i <= 'z')
                i = i - 5;
            else;
    return text;

}


#endif

#include "TextCoder.hpp"
#include <iostream>
#include <string>
int main()
{
    using namespace std;
    string text, encoded_text, decoded_text;
    cout << "输入英文文本: ";
    while (getline(cin, text))
    {
        encoded_text = TextCoder(text).encoder(); // 这里使用的是临时无名对象
        cout << "加密后英文文本:\t" << encoded_text << endl;
        decoded_text = TextCoder(encoded_text).decoder(); // 这里使用的是临时无名对象
        
            cout << "解密后英文文本:\t" << decoded_text << endl;
        cout << "\n输入英文文本: ";
    }
}