Hall Monitor 2

A floor plan is arranged as follows:

• You may freely move between rooms 1 and 2.
• You may freely move between rooms 3 and 4.
• However, you can enter the hallway to move between rooms 2 and 4.

Create a function that validates whether the route taken between rooms is possible. The hallway will be given as the letter "H".

Examples

possible_path([1, 2, "H", 4, 3]) ➞ True

possible_path(["H", 1, 2]) ➞ False

possible_path([4, 3, 4, "H", 4, "H"]) ➞ True

Notes

• A route may begin or end in any room (including the hallway).
• All inputs are either numbers 1-4 or the letter "H".
• No rooms will repeat.