Practice/Uber/Leetcode 1244. Design A Leaderboard

Leetcode 1244. Design A Leaderboard

CodingMust

Problem

You are tasked with implementing a leaderboard system for an online gaming tournament. The leaderboard must efficiently track player scores and support the following operations:

• addScore(playerId, score): Add points to a player's cumulative score. If the player doesn't exist, create a new entry for them.
• top(K): Return the sum of the scores of the top K players (players with the highest scores).
• reset(playerId): Clear a player's score, removing them from the leaderboard entirely.

Your implementation should handle frequent score updates and top-K queries efficiently.

Requirements

1. Implement a Leaderboard class with the three methods described above
2. Player scores are cumulative - calling addScore multiple times for the same player adds to their existing score
3. The top(K) method should return the sum of the K highest scores currently on the leaderboard
4. If there are fewer than K players, return the sum of all existing scores
5. The reset method completely removes a player's score from the leaderboard

Constraints

• 1 ≤ playerId ≤ 10^5
• 1 ≤ score ≤ 100
• 1 ≤ K ≤ total number of players
• At most 1000 total operations will be called
• All inputs are valid (no need to handle invalid player IDs in reset)

Examples

Example 1:

` Operations: addScore(1, 100) addScore(2, 80) addScore(3, 90) top(2)

Output: 190 Explanation: The top 2 scores are 100 (player 1) and 90 (player 3), sum = 190 `

Example 2:

` Operations: addScore(1, 50) addScore(1, 30) addScore(2, 60) top(1)

Output: 80 Explanation: Player 1's cumulative score is 80 (50 + 30), which is the highest `

Example 3:

` Operations: addScore(1, 100) addScore(2, 90) reset(1) top(2)

Output: 90 Explanation: After resetting player 1, only player 2's score of 90 remains `