I am quite new to programming. Despite that I have to write a C++ program
that opens an .xls workbook, selects a specified worksheet and puts data in
specified cells of the worksheet. I have found a document in the Internet
that describes how to use the Excel COM model. Based on this I created a
program that is able o open a specified .xls workbook and put data in
specified cells in the active sheet. However I do not know how to select a
specified worksheet so that I do not put the data in the worksheet that ust
happens to be active when opening the workbook. How to do that?

Here is the code that does what I described:

CoInitialize(NULL);
Excel::_ApplicationPtr xl;
xl.CreateInstance(L"Excel.Application");
xl-Visible = true;
xl-Workbooks-Open(L"C:\\Documents and Settings\\WRO00724\\my
documents\\Visual Studio
2008\\Projects\\Project1\\Excel3\\Excel3\\Example. xls");
Excel::_WorksheetPtr pSheet = xl-ActiveSheet;
Excel::RangePtr pRange = pSheet-Cells;
pRange-Item[2][1] = 0.86;
pRange-Item[3][1] = "test";

What program lines should I include in order to be able to specify the
particular worksheet the data have to go to?