matrix inputmatrix(int m,int n)
{	  
   matrix a(m,n);
   double *zh,value=0.0;
   zh=new double[M];
   int i=0;
   int static j=0;
   /* Note: The number of "zh" must be equal to  
   the size of the matrix(columns*rows) */
   char sh[20];
   cout<<" \nplease input the dir of your matrix "<<(++j)<<" ( matrix.txt )" <<endl;
   cin>>sh;
   ifstream inClientFile(sh,ios::in);
	if(!inClientFile){
		cerr<<"File could not be opened!"<<endl;
		exit(1);   
	}
   while(inClientFile>>value)
   {     
		zh[i]=value;
		i++;
   } 
   a.setdata(zh);
   return a;
   delete zh;
}
matrix inputmatrix(int m,int n,char sh[])
{	  
   matrix a(m,n);
   double *zh,value=0.0;
   zh= new double[M];
   int i=0;
   ifstream inClientFile(sh,ios::in);
	if(!inClientFile){
		cerr<<"File could not be opened!"<<endl;
		exit(1);   
	}
   while(inClientFile>>value)
   {     
		zh[i]=value;
		i++;
   } 
   a.setdata(zh); 
   return a;
   delete zh;
}	

matrix inputmatrix(int n,char sh[])
{	  
   matrix a(n);
   double *zh,value=0.0;
   zh=new double[M];
   int i=0;
   ifstream inClientFile(sh,ios::in);
	if(!inClientFile){
		cerr<<"File could not be opened!"<<endl;
		exit(1);   
	}
   while(inClientFile>>value)
   {     
		zh[i]=value;
		i++;
   } 
   a.setdata(zh); 
   return a;
   delete zh;
}

int outputmatrix(matrix a)
{	  
	int i=0,j=0,m=a.getrows(),n=a.getcols();
	ofstream outClientFile("output.txt",ios::out);
	if(!outClientFile)
	{// overloaded ! operator
		cerr<<"File could not be opened!"<<endl;
		exit(1);   //prototype in stdlib.h
	}
	for(i=0;i<m;i++)
	{   
	    for(j=0;j<n;j++)
		outClientFile<<' '<<a.getele(i,j);
		outClientFile<<'\n';
	}

	return 0;//ofstream destructor closes file
}