Class FoodRatings

  • All Implemented Interfaces:

    
    public final class FoodRatings
    
                        

    2353 - Design a Food Rating System\.

    Medium

    Design a food rating system that can do the following:

    • Modify the rating of a food item listed in the system.

    • Return the highest-rated food item for a type of cuisine in the system.

    Implement the FoodRatings class:

    • FoodRatings(String[] foods, String[] cuisines, int[] ratings) Initializes the system. The food items are described by foods, cuisines and ratings, all of which have a length of n.

    • void changeRating(String food, int newRating) Changes the rating of the food item with the name food.

    • String highestRated(String cuisine) Returns the name of the food item that has the highest rating for the given type of cuisine. If there is a tie, return the item with the lexicographically smaller name.

    Note that a string x is lexicographically smaller than string y if x comes before y in dictionary order, that is, either x is a prefix of y, or if i is the first position such that x[i] != y[i], then x[i] comes before y[i] in alphabetic order.

    Example 1:

    Input

    "FoodRatings", "highestRated", "highestRated", "changeRating", "highestRated", "changeRating", "highestRated"

    [["kimchi", "miso", "sushi", "moussaka", "ramen", "bulgogi", "korean", "japanese", "japanese", "greek", "japanese", "korean", 9, 12, 8, 15, 14, 7], "korean", "japanese", "sushi", 16, "japanese", "ramen", 16, "japanese"]

    Output:

    null, "kimchi", "ramen", null, "sushi", null, "ramen"

    Explanation:

    FoodRatings foodRatings = new FoodRatings(["kimchi", "miso", "sushi", "moussaka", "ramen", "bulgogi"], ["korean", "japanese", "japanese", "greek", "japanese", "korean"], [9, 12, 8, 15, 14, 7]);
    foodRatings.highestRated("korean"); // return "kimchi"
                                        // "kimchi" is the highest rated korean food with a rating of 9.
    foodRatings.highestRated("japanese"); // return "ramen"
                                          // "ramen" is the highest rated japanese food with a rating of 14.
    foodRatings.changeRating("sushi", 16); // "sushi" now has a rating of 16.
    foodRatings.highestRated("japanese"); // return "sushi"
                                          // "sushi" is the highest rated japanese food with a rating of 16.
    foodRatings.changeRating("ramen", 16); // "ramen" now has a rating of 16.
    foodRatings.highestRated("japanese"); // return "ramen"
                                          // Both "sushi" and "ramen" have a rating of 16.
                                          // However, "ramen" is lexicographically smaller than "sushi".

    Constraints:

    • <code>1 <= n <= 2 * 10<sup>4</sup></code>

    • n == foods.length == cuisines.length == ratings.length

    • 1 &lt;= foods[i].length, cuisines[i].length &lt;= 10

    • foods[i], cuisines[i] consist of lowercase English letters.

    • <code>1 <= ratingsi<= 10<sup>8</sup></code>

    • All the strings in foods are distinct.

    • food will be the name of a food item in the system across all calls to changeRating.

    • cuisine will be a type of cuisine of at least one food item in the system across all calls to highestRated.

    • At most <code>2 * 10<sup>4</sup></code> calls in total will be made to changeRating and highestRated.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
    • Field Summary

      Fields 
      Modifier and Type Field Description
    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description
    • Method Summary

      Modifier and Type Method Description
      final Unit changeRating(String food, Integer newRating)
      final String highestRated(String cuisine)
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait