text: function solve() {
      const info = document.querySelector('.info');
      const departButton = document.querySelector('#depart');
      const arriveButton = document.querySelector('#arrive');
      let stopId = 'depot';
      let stopName = 'Depot';
  
      function depart() {
          fetch(`https://judgetests.firebaseio.com/schedule/${stopId}.json`)
              .then(response => response.json())
              .then(response => {
                  stopId = response.next;
                  stopName = response.name;
                  arriveButton.removeAttribute('disabled');
                  departButton.setAttribute('disabled', true);
                  info.textContent = `Next stop ${response.name}`;
              });
      }
  
      function arrive() {
          departButton.removeAttribute('disabled');
          arriveButton.setAttribute('disabled', true);
          info.textContent = `Arriving at ${stopName}`;
      }
  
      return {
          depart,
          arrive
      };
  }
  
  let result = solve();