MBTA

Went well overall.  Didn't have much trouble implementing the data structure.  Wanted to put entire loop asking for user input within a method but I couldn't figure out how to do this since the method involved assigning values to multiple variables and it doesn't appear that you can pass objects by reference in Ruby? Only solution I could think of was having the line and stop both returned in an array and then assigning them to each line and stop variable, but didn't seem worth it.