I guess you never enter the while loop because one of the >> operator calls fails (can’t read the values for some reason). So it might very well be a problem with your file. Copy-pasting the data you provided into a file worked for me, though – maybe there is a problem with new line delimiters (e.g. if the file was created on windows and now you are reading it on linux)? Those are usually tricky and invisible.
I suggest to keep ROOT out of the equation by just compiling and running the program.
You can remove/comment out everything that is not related to opening the file and reading the first line.
Also remove the while loop.
Can you successfully read the first line of the file this way? If not, how many values can you read before you have a problem?