done .

mbta.rb

@@ -1,5 +1,24 @@
 
 # your solution here
-def stops_between_stations
+def SBS(SL,SS,EL,ES)
+    stations{
+        "Red"=>["South Station","Park Street","Kendall",
+            "Central","Harvard", "Porter","Davis","Alewife"],
+        "Green"=>["Government Center", "Park Street", "Boylston",
+            "Arlington", "Copley", "Hynes", "Kenmore"],
+        "Orange"=>["North Station", "Haymarket", "ParkStreet", 
+            "State", "Downtown Crossing", "Chinatown", "Back Bay", 
+            "Forest Hills"]
+    }
+    if SL == EL 
+        total_stops = stations.index(SS) - stations.index(ES)
+    elsif 
 
-end
+end
+
+upper_case_full_names = students.map do |student|
+    full_name = "#{student[:first_name]} #{student[:last_name]}"
+    full_name.upcase
+end
+
+puts upper_case_full_names.inspect

subway.rb

@@ -0,0 +1,24 @@
+$lines{
+    "Red"=>["South Station","Park Street","Kendall","Central","Harvard", "Porter","Davis","Alewife"],
+    "Green"=>["Government Center", "Park Street", "Boylston","Arlington", "Copley", "Hynes", "Kenmore"],
+    "Orange"=>["North Station", "Haymarket", "ParkStreet", "State", "Downtown Crossing", "Chinatown", "Back Bay", "Forest Hills"]
+}
+
+
+def count_stops(line, station1, station2)
+    station1_index = line.index(station1)
+    station2_index = line.index(station2)
+
+    real_stops = []
+    if station1_index <= station2_index
+        real_stops = line[station1_index..station2_index]
+    else
+        real_stops = line[station2_index..station1_index]
+    end
+
+    real_stops.length - 1
+end
+
+def stops_between_stations(start_line, start_station, end_line, end_stations)
+
+end