rent 2.0: now featuring comments!

rent_improved.js

// Enter data here:
const total_rent = 0;

// A measure of the relative quality between different rooms in the same type.
// Probably will just go with area for these, but if theres like e.g. a really
//  shitty bathroom no one wants to use, it might make sense to lower its quality
// NOTE: quality of two different types (e.g. a bedroom and bathroom) have nothing
//       to do with each other and will never be compared. Because of this, rooms
//       that are one-of-a-type can have their quality left null
const room_qualities = {
  bedroom_1: null,
  bedroom_2: null,
  bedroom_3: null,
  bathroom_1: null,
  bathroom_2: null,
  kitchen_1: null,
  livingroom_1: null,
  livingroom_2: null,
  livingroom_3: null,
  gym_1: null,
  patio_1: null,
  laundry_1: null,
}

// Weights for the total rent should be split up by room. E.g. if everyone decides
//  bedroom size/quality is the most important factor in rent-paying, bedrooms should
//  be weighted higher
const room_type_weights = {
  bedroom: 0.45,
  bathroom: 0.20,
  kitchen: 0.05,
  livingroom: 0.07,
  patio: 0.03,
  yard: 0.10,
  laundry: 0.03,
  gym: 0.07,
}
// NOTE: weights must sum to one. just in case, they will be normalized here:
let room_type_weight_sum = 0;
for (const type in room_type_weights) {
  room_type_weight_sum += room_type_weights[type];
}

for (const type in room_type_weights) {
  room_type_weights[type] /= room_type_weight_sum;
}

// For each room, list all people who have "ownership" over that room. e.g. two
//  people sharing a bathroom would both be in that bathroom's list. someone with
//  their own bedroom should be the only person in that bedroom's list.
// To make life easier and help prevent typos, make consts for each person, e.g.
// const a = 'alice';
// const b = 'bob';
// const c = 'cathy';
// etc.
const room_shares = {
  bedroom_1: [],
  bedroom_2: [],
  bedroom_3: [],
  bathroom_1: [],
  bathroom_2: [],
  kitchen_1: [],
  livingroom_1: [],
  patio_1: [],
  laundry_1: [],
}


// And then the magic happens

// Generate a map from room types to a list of specific rooms of that type
const room_type_map = {};
for (const room in room_shares) {
  const type = room.split('_')[0];
  if (typeof room_type_map[type] === 'undefined') {
    room_type_map[type] = [];
  }

  room_type_map[type].push(room);
}

// Calculate the percentage of each room type associated with each room of that type
const room_percents = {}
for (const type in room_type_map) {
  const rooms = room_type_map[type]
  if (room_qualities[rooms[0]] === null) {
    for (const room of rooms) {
      room_percents[room] = room_type_weights[type] * 1/room_type_map[type].length;
    }
  } else {
    let sum = rooms.slice().map(room => room_qualities[room]).reduce((a, b) => a+b);
    console.log(sum);

    for (const room of rooms) {
      room_percents[room] = room_type_weights[type] * room_qualities[room]/sum;
    }
  }
}

// Calculate how much of each room each person "owns"
const person_shares = {}
for (const room in room_shares) {
  const people = room_shares[room];
  for (let person of people) {
    if (typeof person_shares[person] === 'undefined') {
      person_shares[person] = 0;
    }

    person_shares[person] += room_percents[room] / people.length
  }
}

// Map those ownership percentages to the total rent
const final_rents = {}
for (const person in person_shares) {
  const exact_rent = total_rent * person_shares[person];
  final_rents[person] = Math.round(exact_rent*100)/100; // round to the nearest cent
}

// The moment of truth:
console.log(final_rents);