How can I read a file (in any directory) which name(only file.txt) is passed as parameter? C++

Question

I want to follow this schema:

    //Read filename
    string filename; 
cout << "ONLY Name of the file you want to read, not directory: "; 
cin >> filename;

    //Find file in disk C and open it
    ifstream ifs(.................);
    while( int cc = FileRead( ifs, buff ) ) {
       etc. (trivial)
    }

Answer 1

ifstream ifs(filename.c_str());

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