Design a Food Rating System LeetCode solution in Java

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class FoodRatings {
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  HashMap<String, TreeSet<String>> cuiToFood = new HashMap();
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  HashMap<String, Integer> foodToRat = new HashMap();
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  HashMap<String, String> foodToCui = new HashMap();
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  public FoodRatings(String[] foods, String[] cuisines, int[] ratings) {
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    for (int i = 0; i < foods.length; i++) {
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      TreeSet<String> foodOfThisCuisine =
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          cuiToFood.getOrDefault(
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              cuisines[i],
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              new TreeSet<String>(
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                  (a, b) ->
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                      foodToRat.get(a).equals(foodToRat.get(b))
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                          ? a.compareTo(b)
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                          : foodToRat.get(b) - foodToRat.get(a)));
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      // Both comparators are equal
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      /* new Comparator<String>(){
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                   @Override
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                   public int compare(String a, String b){
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                       int aRat = foodToRat.get(a);
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                       int bRat = foodToRat.get(b);
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                       if(aRat != bRat) return bRat - aRat; // largest rating first
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                       for(int i = 0; i < Math.min(a.length(), b.length()); i++){
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                           if(a.charAt(i) != b.charAt(i)) return a.charAt(i) - b.charAt(i);
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                       }
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                       return a.length() - b.length();
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                   }
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               })
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      */
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      foodToRat.put(foods[i], ratings[i]);
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      foodOfThisCuisine.add(foods[i]);
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      foodToCui.put(foods[i], cuisines[i]);
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      cuiToFood.put(cuisines[i], foodOfThisCuisine);
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    }
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  }
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  // CompareTo() is used to compare whether 2 strings are equal in hashSet! So remove, change value
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  // of key in HashMap, then insert again
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  public void changeRating(String food, int newRating) {
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    String cui = foodToCui.get(food);
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    TreeSet<String> foodOfThisCui = cuiToFood.get(cui);
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    foodOfThisCui.remove(food);
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    foodToRat.put(food, newRating);
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    foodOfThisCui.add(food);
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    cuiToFood.put(cui, foodOfThisCui);
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  }
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  public String highestRated(String cuisine) {
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    return cuiToFood.get(cuisine).first();
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  }
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}