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#include<iostream>
#include<iomanip>
using namespace std;
class String{
friend ostream& operator<< (ostream&??String&);//????<<?????
friend istream& operator>> (istream&??String&);//????>>?????
public:
String(const char* str=NULL);                //????????????????(char)
String(const String &other);                 //?????????(String)
String& operator=(const String& other);       //operator=
String operator+(const String &other)const;  //operator+
bool operator==(const String&);              //operator==
char& operator[](unsigned int);              //operator[]
size_t size(){return strlen(m_data);};
~String(void) {delete[] m_data;}
private:
char *m_data; // ????????????
};
inline String::String(const char* str)
{
if(!str)m_data=0;      //?????inline????????ú?????????б??????????????滻?????????????
else {
m_data=new char[strlen(str)+1];
strcpy(m_data??str);
}
}
inline String::String(const String &other)
{
if(!other.m_data)m_data=0;//????????????????????????????г?????????????????????
else
{
m_data=new char[strlen(other.m_data)+1];
strcpy(m_data??other.m_data);
}
}
inline String& String::operator=(const String& other)
{
if (this!=&other)
{
delete[] m_data;
if(!other.m_data) m_data=0;
else
{
m_data = new char[strlen(other.m_data)+1];
strcpy(m_data??other.m_data);
}
}
return *this;
}
inline String String::operator+(const String &other)const
{
String newString;
if(!other.m_data)
newString = *this;
else if(!m_data)
newString = other;
else
{
newString.m_data = new char[strlen(m_data)+strlen(other.m_data)+1];
strcpy(newString.m_data??m_data);
strcat(newString.m_data??other.m_data);
}
return newString;
}
inline bool String::operator==(const String &s)
{
if ( strlen(s.m_data) != strlen(m_data) )
return false;
return strcmp(m_data??s.m_data)?false:true;
}
inline char& String::operator[](unsigned int e)
{
if (e>=0&&e<=strlen(m_data))
return m_data[e];
}
ostream& operator<<(ostream& os??String& str)
{
os << str.m_data;
return os;
}
istream &operator>>( istream &input?? String &s )
{
char temp[ 255 ]; //????洢??????
input>>setw(255)>>temp;
s = temp; //??????????
return input; //???return??????????????>>?????
}
int main()
{
String str1="Aha!";
String str2="My friend";
String str3 = str1+str2;
cout<<str3<<"/n"<<str3.size()<<endl;
return 0;
}