O(1) Insert, Remove, and Weighted Random Retrieval Class

bytedance Implement a class with the following methods: insert(number): Returns false if the number already exists; otherwise, inserts the number and returns true. remove(number): Returns false if the number doesn't exist; otherwise, removes the number and returns true. getRandom(): Returns a random number based on weight, with equal probability for each number. All methods must work in O(1) time complexity. Please design and implement this class, and provide at least 5 test cases. Example Input insert 1 insert 1 remove 1 remove 2 insert 2 getRandom