You are with your friends in a castle, where there are multiple rooms named after flowers. Some of the rooms contain treasures - we call them the treasure rooms. Each room contains a single instruction that tells you which room to go to next. *** instructions_1 and treasure_rooms_1 *** lily* --------- daisy sunflower | | | v v v jasmin --> tulip* violet* ----> rose* --> ^ | ^ ^ | | | | | | ------ iris --------- * denotes a treasure room, e.g., rose is a treasure room, but jasmin isn't. This is given as a list of pairs of (source_room, destination_room) instructions_1 = [ ["jasmin", "tulip"], ["lily", "tulip"], ["tulip", "tulip"], ["rose", "rose"], ["violet", "rose"], ["sunflower", "violet"], ["daisy", "violet"], ["iris", "violet"] ] treasure_rooms_1 = ["lily", "tulip", "violet", "rose"] Write a function that takes two parameters as input: * a list of instructions represented as pairs of (source_room, destination_room), and * a list containing the treasure rooms, and returns a collection of all the rooms that satisfy the following two conditions: * at least two *other* rooms have instructions pointing to this room * this room's instruction immediately points to a treasure room filter_rooms(instructions_1, treasure_rooms_1) => ["tulip", "violet"] * tulip can be accessed from rooms lily and jasmin. Tulip's instruction points to a treasure room (tulip itself) * violet can be accessed from daisy, sunflower and iris. Violet's instruction points to a treasure room (rose) Additional inputs treasure_rooms_2 = ["lily", "jasmin", "violet"] filter_rooms(instructions_1, treasure_rooms_2) => [] * none of the rooms reachable from tulip or violet are treasure rooms *** instructions_2 and treasure_rooms_3 *** lily --------- -------- | | | v v | jasmin --> tulip ---> violet*--^ instructions_2 = [ ["jasmin", "tulip"], ["lily", "tulip"], ["tulip", "violet"], ["violet", "violet"] ] treasure_rooms_3 = ["violet"] filter_rooms(instructions_2, treasure_rooms_3) => ["tulip"] * tulip can be accessed from rooms lily and jasmin. Tulip's instruction points to a treasure room (violet) All the test cases: filter_rooms(instructions_1, treasure_rooms_1) => ["tulip", "violet"] filter_rooms(instructions_1, treasure_rooms_2) => [] filter_rooms(instructions_2, treasure_rooms_3) => ["tulip"] Complexity Analysis variables: T: number of treasure rooms I: number of instructions given