2353. Design a Food Rating System: RETRY

Author: tan-wei

src/solution/mod.rs

@@ -1783,3 +1783,4 @@ mod s2349_design_a_number_container_system;
 mod s2350_shortest_impossible_sequence_of_rolls;
 mod s2351_first_letter_to_appear_twice;
 mod s2352_equal_row_and_column_pairs;
+mod s2353_design_a_food_rating_system;

src/solution/s2353_design_a_food_rating_system.rs

@@ -0,0 +1,130 @@
+/**
+ * [2353] Design a Food Rating System
+ *
+ * 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.
+ *
+ * 		foods[i] is the name of the i^th food,
+ * 		cuisines[i] is the type of cuisine of the i^th food, and
+ * 		ratings[i] is the initial rating of the i^th food.
+ *
+ *
+ * 	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:
+ *
+ * 	1 <= n <= 2 * 10^4
+ * 	n == foods.length == cuisines.length == ratings.length
+ * 	1 <= foods[i].length, cuisines[i].length <= 10
+ * 	foods[i], cuisines[i] consist of lowercase English letters.
+ * 	1 <= ratings[i] <= 10^8
+ * 	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 2 * 10^4 calls in total will be made to changeRating and highestRated.
+ *
+ */
+pub struct Solution {}
+
+// problem: https://leetcode.com/problems/design-a-food-rating-system/
+// discuss: https://leetcode.com/problems/design-a-food-rating-system/discuss/?currentPage=1&orderBy=most_votes&query=
+
+// submission codes start here
+
+struct FoodRatings {}
+
+/**
+ * `&self` means the method takes an immutable reference.
+ * If you need a mutable reference, change it to `&mut self` instead.
+ */
+impl FoodRatings {
+    fn new(foods: Vec<String>, cuisines: Vec<String>, ratings: Vec<i32>) -> Self {
+        Self {}
+    }
+
+    fn change_rating(&self, food: String, new_rating: i32) {
+        //
+    }
+
+    fn highest_rated(&self, cuisine: String) -> String {
+        String::new()
+    }
+}
+
+/**
+ * Your FoodRatings object will be instantiated and called as such:
+ * let obj = FoodRatings::new(foods, cuisines, ratings);
+ * obj.change_rating(food, newRating);
+ * let ret_2: String = obj.highest_rated(cuisine);
+ */
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn test_2353_example_1() {
+        let mut food_ratings = FoodRatings::new(
+            vec_string!["kimchi", "miso", "sushi", "moussaka", "ramen", "bulgogi"],
+            vec_string![
+                "korean", "japanese", "japanese", "greek", "japanese", "korean",
+            ],
+            vec![9, 12, 8, 15, 14, 7],
+        );
+        assert_eq!(
+            food_ratings.highest_rated("korean".to_string()),
+            "kimchi".to_string()
+        );
+
+        assert_eq!(
+            food_ratings.highest_rated("japanese".to_string()),
+            "ramen".to_string()
+        );
+
+        food_ratings.change_rating("sushi".to_string(), 16);
+        assert_eq!(
+            food_ratings.highest_rated("japanese".to_string()),
+            "sushi".to_string()
+        );
+
+        food_ratings.change_rating("ramen".to_string(), 16);
+        assert_eq!(
+            food_ratings.highest_rated("japanese".to_string()),
+            "ramen".to_string()
+        );
+    }
+}