Unable to read .txt file using Command Line in c++ -

i trying read .txt file looks "-f filename.txt". project working on requires me name of file after "-f", open file name , extract information vector string.

i able except extraction. reason won't open file.

here code:

int main(int argc, char* argv[]) {     ifstream file;     string line;     vector <string> lines;     (int i=0; i<argc; i++)     {         if (strcmp( argv[1], "-f" )==0)         {             cout << "i here" << endl;             std::string argv2 = argv[2];             cout << argv2 << endl;              file.open(argv2.c_str());              if(!file.is_open())             {                cout << "file failed open" << endl;             }             while (getline(file, line))              {                 lines.push_back(line);             }          }     }      (unsigned int j=0; j<lines.size(); j++)     {         cout << lines[j] << endl;     }   

my output

i here test.txt file failed open 

x3

i don't because file.open(argv2.c_str()); worked when put string filename instead of argv2 both strings... right?

the -f test.txt file under project folder , test.txt under debug folder. added -f test.txt in program arguments.

if run ide visual studio default current directory when running not executable file is, project root directory.

either change arguments -f debug\test.txt, or move file project root directory.