Visual C++ :: Enter File Name By Keyboard Instead Of Command Line Arguments?

Actually the below program is for Dispersal Algorithm called Rabin-IDA; this algorithm divided the data into N pieces and then recombine it from M pieces (such that M<N).

Thus, the below program needs command line arguments,which entering by Project properties/Debugging. this argument is file name, where the program performing spitted the file into N files, and then recombine it from M divided files, and put it on another file which should also passing its name as argument .

Now my question is, How can i make this program enter the file name by keyboard??(i mean enter the files name by user from screen not as command line arguments) ... In another word, How I can exchange ?

Code:
argc == 3
and
Code:
argc == 2

To enter file name ? i mean what i should do to in

Code:
rabin.split(argv[1])

To pass my file name by use keyboard not Project properties/Debugging?)

the below code is just the main function of program, and the whole of it in this link [URL] .... Information Dispersal Algorithms Rabin-IDA.

Code:
#include "include.h"
void __cdecl _tmain(int argc, TCHAR *argv[]) {
DWORD ini=GetTickCount();
try {
if( argc == 3 ) //recombine

[Code] ....

I know I should use getline() function but how exchange argv[] ?