If your ifstream constructor doesn't allow std::strings as a parameter, try to update your compiler.
Make sure that you are using the c++11 standard (for g++, is the `-std=c++11' flag)
Ok, I got it to where it had no errors, and I got it running. When asked the file name, I typed sal.txt. Although when the program ends, I opened the projects file location and there was no file named 'sal' in the folder. Is there something I did wrong?
I'd make sure that folder is actually considered the working directory for when you run the executable. You could try putting in an absolute path also.