[CODE]
#include<iostream>
#include <cstring>
#include <string>
using namespace std;
class DMA
{
private:
	    enum{max=20};
		char  *mString;
public:
	DMA(char *s="none"); 
	~DMA();
	DMA(const DMA & addString);
	DMA & operator=(const DMA & addString);
    void operator+( char * catStr);
	friend std::ostream & operator<<(std::ostream & os,const DMA & rs);
};
DMA::DMA(char *s)
{	
	int len=strlen(s);
	mString=new char[len+1];
	strcpy(mString,s);
}
DMA::~DMA()
{
	delete[] mString;
}
DMA::DMA(const DMA & addString)
{
		int len=strlen(addString.mString);
		mString=new char[len+1];
		strcpy(mString,addString.mString);
}
DMA & DMA::operator=(const DMA & addString)
{
		if (this==&addString)
			return *this;
		delete[]mString;
		int len=strlen(addString.mString);
		mString=new char[len+1];
		strcpy(mString,addString.mString);
		return *this;
}
void DMA::operator+( char * catStr)
{
		int Lstr=strlen(catStr);
		int LMstr=strlen(this->mString);
		mString=new char[(Lstr+LMstr)+2];
		strcat(this->mString,catStr);
}
ostream & operator<<(ostream & os,const DMA &rs)
{
	os<<rs.mString<<endl;
	return os;
} 
int main()
{
	DMA sOne("woshi");
	 sOne+"Pogramer";
    	cout<<sOne ;
	return 0;
}

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