实验3

#include "info.hpp"
#include <iostream>
#include<vector>
#include<cstring>
int main()
{
    int count=0;
    const int capacity=100;
    vector<Info>audience_info_list;
    cout << "录入信息:" << endl << endl;
    cout << "昵称     "  << "联系方式（邮箱/手机号）     "  << "所在城市     " << "预定参加人数    " << endl;
    string x,y,z; int k;
    string s;
    while(cin>>x)
    {
        cin>>y>>z>>k;
        Info info(x,y,z,k);
        audience_info_list.push_back(info);
        count+=k;
        if(count>capacity)
        {
            count=count-k;
            audience_info_list.pop_back();
            cout<<"对不起，只剩"<<capacity-count<<"个位子。"<<endl; 
            cout<<"1.输入u，更新（update）预定信息。"<<endl;
            cout<<"2.输入q，退出预定。" <<endl;
            cout << "你的选择 ：";
            cin>>s;
            if(s=="u")
            continue;
            if(s=="q")
            break;
        }
        if(count==capacity)
        break;    
    }
        cout <<endl<< "截止目前，一共有" << count << "位听众预定参加。预定听众信息如下：" << endl;
        for (auto &item : audience_info_list)
    {
        item.print();
    }
    return 0;
}

#include<iostream>
#include<cstring>

using namespace std;

class Info
{
public:
    Info(string x,string y,string z,int k):nickname{x},contact{y},city{z},n{k}{}
    void print();
private:
string nickname,contact,city;
int n;        
};

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

task2：

#pragma once

#include <iostream>
#include <string>
using namespace std;

class TextCoder
{
private:
    string text;

public:
    TextCoder(string x):text{x}{}
    string get_ciphertext();
    string get_deciphertext();

private:
    void encoder(string &s)
    {
        for (auto &i : s)
        {
            if (isalpha(i))
            {
                i += 5;
                if (i > 'z'||i<'a'&&i>'Z')
                i -= 26;
            }
        }
    }
    void decoder(string &s)
    {
        for (auto &i : s)
        {
            if (isalpha(i))
            {
                i -= 5;
                if (i < 'A'||i>'Z'&&i<'a')
                i += 26;
            }
        }
    }
};
string TextCoder::get_ciphertext()
{
    encoder(text);
    return text;
}

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