text: function solve() {
      const URL = "https://judgetests.firebaseio.com/schedule";
  
      let nextStationId  = "depot";
      let stationName = "";
  
      function depart() {
          $("#depart").prop('disabled',true);
          $("#arrive").prop('disabled',false);
  
          $.ajax({
              url:URL + `/${nextStationId}.json`,
          }).then(displayResult)
              .catch(displayErrors)
  
          function displayResult(response) {
              $(".info").text("Next Stop " +response.name);
  
              nextStationId = response.next;
              stationName = response.name;
          }
  
          function displayErrors(err) {
              $("#depart").prop('disabled',true);
              $("#arrive").prop('disabled',true);
  
              $(".info").text("Error");
  
          }
  
      }
  
      function arrive() {
          $("#depart").prop('disabled',false);
          $("#arrive").prop('disabled',true);
          $(".info").text("Arriving at " +stationName);
      }
      return {
          depart,
          arrive
      };
  }
  let result = solve();