for ( size_t i = 5; i < 50; i = i + 5)
{
	std::wostringstream wout;	
	wout<<L"tmp_name"<<i;
	std::wofstream of (wout.str().c_str(), std::ios::out);
	of<<"Something was written"<<std::endl;
	of.close();
};

for ( size_t i = 5; i < 50; i = i + 5)
{
	std::wstring tmpr=L"tmp_name";
	wchar_t u[5];
	tmpr+=_itow(i, u, 10);
	std::wofstream of (tmpr.c_str(), std::ios::out);
	of<<"Something was written"<<std::endl;
	of.close();
};

char filename [] = "1_matrix.xls";
static char f = '1';
filename[0] = f; f++;
FILE *fMATRIX=fopen(filename,"w");
	//печать
	for (int i=0; i<m; i++) {
		for (int j=0; j<m; j++) {
			fprintf(fMATRIX, "%lf\t%", mtr[i][j]);
		}
		fprintf(fMATRIX, "\n");
	}
fclose(fMATRIX);