Design a Food Rating System LeetCode solution in JavaScript

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var FoodRatings = function (foods, cuisines, ratings) {
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  (this.heaps = {}), (this.foods = {});
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  let n = foods.length;
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  for (let i = 0; i < n; i++) {
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    let food = foods[i],
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      cuisine = cuisines[i],
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      rating = ratings[i];
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    if (!this.heaps[cuisine])
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      this.heaps[cuisine] = new PriorityQueue((a, b) => {
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        // [food, rating]
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        return a[1] === b[1] ? a[0].localeCompare(b[0]) : b[1] - a[1];
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      });
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    this.heaps[cuisine].add([food, rating]);
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    this.foods[food] = { cuisine, rating };
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  }
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};
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FoodRatings.prototype.changeRating = function (food, newRating) {
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  this.foods[food].rating = newRating;
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  let { cuisine } = this.foods[food];
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  this.heaps[cuisine].add([food, newRating]);
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};
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FoodRatings.prototype.highestRated = function (cuisine) {
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  let heap = this.heaps[cuisine];
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  while (this.foods[heap.top()[0]].rating !== heap.top()[1]) {
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    heap.remove();
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  }
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  return heap.top()[0];
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};
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class PriorityQueue {
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  constructor(comparator = (a, b) => a - b) {
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    this.values = [];
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    this.comparator = comparator;
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    this.size = 0;
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  }
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  add(val) {
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    this.size++;
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    this.values.push(val);
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    let idx = this.size - 1,
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      parentIdx = Math.floor((idx - 1) / 2);
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    while (
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      parentIdx >= 0 &&
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      this.comparator(this.values[parentIdx], this.values[idx]) > 0
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    ) {
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      [this.values[parentIdx], this.values[idx]] = [
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        this.values[idx],
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        this.values[parentIdx],
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      ];
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      idx = parentIdx;
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      parentIdx = Math.floor((idx - 1) / 2);
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    }
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  }
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  remove() {
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    if (this.size === 0) return -1;
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    this.size--;
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    if (this.size === 0) return this.values.pop();
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    let removedVal = this.values[0];
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    this.values[0] = this.values.pop();
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    let idx = 0;
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    while (idx < this.size && idx < Math.floor(this.size / 2)) {
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      let leftIdx = idx * 2 + 1,
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        rightIdx = idx * 2 + 2;
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      if (rightIdx === this.size) {
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        if (this.comparator(this.values[leftIdx], this.values[idx]) > 0) break;
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        [this.values[leftIdx], this.values[idx]] = [
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          this.values[idx],
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          this.values[leftIdx],
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        ];
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        idx = leftIdx;
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      } else if (
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        this.comparator(this.values[leftIdx], this.values[idx]) < 0 ||
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        this.comparator(this.values[rightIdx], this.values[idx]) < 0
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      ) {
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        if (this.comparator(this.values[leftIdx], this.values[rightIdx]) <= 0) {
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          [this.values[leftIdx], this.values[idx]] = [
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            this.values[idx],
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            this.values[leftIdx],
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          ];
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          idx = leftIdx;
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        } else {
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          [this.values[rightIdx], this.values[idx]] = [
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            this.values[idx],
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            this.values[rightIdx],
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          ];
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          idx = rightIdx;
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        }
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      } else {
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        break;
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      }
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    }
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    return removedVal;
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  }
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  top() {
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    return this.values[0];
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  }
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  isEmpty() {
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    return this.size === 0;
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  }
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}