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#include <cstring>
#include <iostream>
#include <fstream>

using namespace std;

class buffer {
char* buff;
int size;
public:
buffer():buff(0),size(0){}
buffer(const buffer&);
buffer& operator=(const buffer&);
buffer& operator+=(const buffer&);
bool operator==(const buffer&);
buffer& buffer:: operator+=( const char*);
buffer& buffer:: operator=(const char*);
bool buffer:: operator==(const char*);
friend void beolvas(buffer &);
friend void kiir(buffer &);
friend ostream& operator<<(ostream& s, const buffer b);
friend istream& operator>>(istream& s, const buffer b);
~buffer(){ delete[] buff; }

};

buffer::buffer(const buffer& e)
{
buff=new char[(size=e.size)+1];
if (e.buff)
strcpy(buff,e.buff);
}

buffer& buffer:: operator+=( const char* value)
{
char* temp=new char[size = strlen(buff)+ strlen(value) +1];
strcpy(temp,buff);
strcat(temp, value);
delete[] buff;
buff = temp;
return *this;
}

buffer& buffer:: operator+=(const buffer& e)
{
char* temp=new char[size+=(e.size+1)];
strcpy(temp,buff);
strcat(temp,e.buff);
delete[] buff;
buff=temp;
return *this;
}

buffer& buffer:: operator=(const char* value)
{
delete[] buff;
if( size=strlen(value))
{
buff=new char[size+1];
strcpy(buff,value);
}
return *this;
}


buffer& buffer:: operator=(const buffer& e)
{
if( this!= &e)
{
delete[] buff;
buff=new char[size=e.size];
strcpy(buff,e.buff);
}
return *this;
}

bool buffer:: operator==(const char* value)
{
if(size==strlen(value)) return true;

else return false;
}


bool buffer:: operator==(const buffer& e)
{
if(size==e.size) return true;

else return false;
}

ostream& operator<<(ostream& s, const buffer b)
{
for(int i=0;i<b.size;++i)
{
s<<b.buff;
}
return (s);

}

int karakterek_szama()
{
fstream fp(''c:\\txt.txt'',ios::in);
char c;
int k=0;
while(!fp.eof())
{
fp.get(c);
++k;
}
fp.close();
return k;
}

istream& operator>>(istream& s, buffer b)
{
int k=karakterek_szama();
delete[] b.buff;
b.buff=new char[(b.size=k)+1];
for(int i=0;i<b.size;++i)
{
s>>b.buff;
}
return (s);

}

void beolvas(buffer& b)
{
int k=karakterek_szama();
delete[] b.buff;
b.buff=new char[(b.size=k)+1];
fstream fp(''c:\\txt.txt'',ios::in);
while(!fp.eof())
{
fp.getline(b.buff,b.size);
}
fp.close();
}

void kiir(buffer& b)
{
fstream fp(''c:\\txt.txt'',ios:ut);
fp<<b.buff;
fp.close();
}

int main()
{
buffer b;
buffer a;
beolvas(b);
char s[7]=''+FUZES'';
char s2[11]=''ASDFWERGWE'';
a=s2;
cout<<(a==b);
cout<<endl;
b+=s;
cout<<b;
cout<<endl;
b+=a;
cout<<b;
kiir(b);
cin.get();
return 0;
}

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