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

class mystring
{
private:
    char *str;   //记录C风格字符串
    int size;    //记录字符串的实际长度

public:
    //无参构造
    mystring():size(10)
    {
        str=new char[size];//构造出一个长度为10的字符串
        strcpy(str,"");//赋值为空串
    }
    //有参构造
    mystring(const char *s)
    {
        size=strlen(s);
        str=new char[size+1];
        strcpy(str,s);
    }

    //拷贝构造
    mystring (const mystring &other):str(new char(*(other.str))),
        size(other.size)
    {
        strcpy(this->str,other.str);
    }
    //析构函数
    ~mystring()
    {
        delete []str;
        str=nullptr;
    }
    //拷贝赋值函数
    mystring &operator=(const mystring &other)
    {
        if(this!=&other)
        {
            this->size=other.size;
            this->str=new char[size+1];
            strcpy(str,other.str);
        }
        return *this;
    }
    //判空函数
    bool mystring_empty(char *s)
    {
        if(strlen(s)==0)
            return 1;
        else
            return 0;
    }
    //size函数
    void mystring_size()
    {
        cout<<strlen(str)<<endl;
    }
    //c_ str函数
    char *c_str()
    {
        return str;
    }
    //at函数
    char &mystring_at(int pos)
    {
        return this->str[pos];
    }

    //加号运算符重载
    const mystring operator+(const mystring &R)const
    {
        mystring temp;
        strcpy(temp.str,strcat(this->str,R.str));
        return temp;
    }

    //关系运算符重载(>)
    bool operator>(const mystring &R)const
    {
        if(strcmp(this->str,R.str)>=0)
            return 1;
        else
            return 0;
    }
    //加等于运算符重载
     mystring &operator+= (const mystring &R)
    {
       strcat(this->str,R.str);
        return *this;
    }
    void show()
    {
       cout<<str<<endl;
    }

};
int main()
{
    mystring s1("hello");
    s1.show();
    s1.mystring_size();
    cout<<s1.mystring_at(2)<<endl;

    mystring s2;
    s2=s1;
    s2.show();

    mystring s3=s2+s1;
    s3.show();

    mystring s4;
    s4+=s1;
    s4.show();

    if(s3>s1)
    {
        cout<<"yes"<<endl;
    }
    else
        cout<<"no"<<endl;

    return 0;
}