If you know a certain c++ library treat with excel sheet with efficient way that can read acertain row or columns Support me by it
I always avoid using the .xls if possible. .xml is fairly easy to read and write with c++. Be careful though, because the xml file will change in unexpected ways if you do something in excel.
The easiest way to do it in C/C++ is to load Excell and export the data to a text file, manipulate that text file, then input it back into Excel.
How i do that
save the file as a .txt file or a .CSV (comma separated value) file. I disagree that this is the easiest though, but that's a matter of opinion.