完成mystring类部分功能实现
代码：
/*******************************************/
文件名：work4.h
/*******************************************/
#ifndef WORK4_H
#define WORK4_H
#include <iostream>
#include<cstring>
using namespace std;
class Mystring
{
private:char *buf;
public:static int count;
public:Mystring(){buf = new char[1];*buf = '\0';count++;}Mystring(const char *b);~Mystring(){delete[] buf;count--;}void show(){cout<<buf<<endl;}const Mystring &operator=(const Mystring &R);char at(int index);const Mystring operator[](int index);char data();const Mystring c_str();bool empty();int size()const;int length()const;int capacity()const;bool clear();bool push_back(char s);bool pop_balck();bool append(char s);Mystring &operator+=(const Mystring &R);const Mystring operator+(const Mystring &R);bool operator==(const Mystring &R);bool operator!=(const Mystring &R);bool operator>(const Mystring &R);bool operator>=(const Mystring &R);bool operator<=(const Mystring &R);friend ostream & operator<<(ostream &L, const Mystring &R);friend istream & operator>>(istream &L, Mystring &R);
};#endif // WORK4_H/*******************************************/
文件名：work4.cpp
/*******************************************/
#include"work4.h"
int Mystring::count = 0;
Mystring::Mystring(const char *b)
{int len=strlen(b);this->buf = new char[len + 1];strcpy(this->buf, b);count++;
}
const Mystring &Mystring::operator=(const Mystring &R)
{delete[] buf;buf = new char[std::strlen(R.buf) + 1];std::strcpy(buf, R.buf);return *this;
}
char Mystring::at(int index)
{if (index < 0 || index >= (int)strlen(buf)) {throw std::out_of_range("Index out of range");}return this->buf[index];
}
const Mystring Mystring::operator[](int index)
{return Mystring(&buf[index]);
}
char Mystring::data()
{return *this->buf;
}
const Mystring Mystring::c_str()
{return *this;
}
bool Mystring::empty()
{return "this->buf=='\0'";
}
int Mystring::size()const
{return strlen(this->buf);
}
int Mystring::length()const
{return size();
}
int Mystring::capacity()const
{return strlen(this->buf)+1;
}
bool Mystring::clear()
{delete[]this->buf;this->buf=new char[1];*buf='\0';return 1;
}
bool Mystring::push_back(char s)
{char *newBuf = new char[capacity() + 1];std::strcpy(newBuf, this->buf);newBuf[size()] = s;newBuf[size() + 1] = '\0';delete[] this->buf;buf = newBuf;return 1;
}
bool Mystring::pop_balck()
{if (empty()){return 0;}char *newBuf = new char[size() + 1];std::strncpy(newBuf, this->buf, size() - 1);newBuf[size() - 1] = '\0';delete[] this->buf;buf = newBuf;return 1;
}
bool Mystring::append(char s)
{return push_back(s);
}
Mystring &Mystring::operator+=(const Mystring &R)
{*this = *this + R;return *this;
}
const Mystring Mystring::operator+(const Mystring &R)
{Mystring temp;temp.buf = new char[size() + R.size() + 1];strcpy(temp.buf, buf);strcat(temp.buf, R.buf);return temp;
}
bool Mystring::operator==(const Mystring &R)
{return strcmp(buf, R.buf) == 0;
}
bool Mystring::operator!=(const Mystring &R)
{return !(*this == R);
}
bool Mystring::operator>(const Mystring &R)
{return strcmp(this->buf, R.buf) > 0;
}
bool Mystring::operator>=(const Mystring &R)
{return *this > R || *this == R;
}
bool Mystring::operator<=(const Mystring &R)
{return !(*this > R);
}
ostream & operator<<(ostream &L, const Mystring &R)
{L << R.buf;return L;
}
istream & operator>>(istream &L, Mystring &R)
{L>>R.buf;return L;
}
/*******************************************/
文件名：main.cpp
/*******************************************/
#include"work4.h"int main()
{Mystring s1="hello";s1.show();Mystring s2="world!";s2.show();Mystring s3=s1+s2;s3.show();cout<<s1.size()<<endl;cout<<s2.length()<<endl;cout<<s3.capacity()<<endl;cout<<s2.at(3)<<endl;cout<<s1.data()<<endl;cout<<s3.append('e')<<endl;cout<<s2.c_str()<<endl;s3.pop_balck();cout<<s3<<endl;s3.push_back('.');cout<<s3<<endl;Mystring s4="ssr";s4+="'a'";cout<<s4<<endl;Mystring s5;cout<<"请输入：";cin>>s5;cout<<s5<<endl;cout<<(s5>=s3)<<endl;return 0;
}
结果：
思维导图：
