Win condition checking in LLD - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Identifying Win Condition Triggers

In a turn-based game, which event should trigger the win condition check to ensure the game ends promptly and correctly?

A After each player's move is fully processed and the game state is updated.

B Only at the start of the game before any moves are made.

C Randomly at fixed time intervals regardless of player actions.

D Only after all players have taken their turns in a round.

💡 Hint

Think about when the game state changes and when it makes sense to check if someone has won.

Win conditions should be checked immediately after a player's move to promptly detect a winner and end the game without unnecessary delays.

❓ Architecture

intermediate

Designing a Win Condition Checker Component

Which design best supports scalability and maintainability for a win condition checker in a multiplayer online game?

A A monolithic server that handles all game logic including win checks without modularization.

B Embedding win condition logic directly inside the player client application.

C Win condition checks performed manually by players through UI prompts.

D A separate stateless service that receives game state snapshots and returns win status.

💡 Hint

Consider separation of concerns and how to handle many simultaneous games efficiently.

A stateless service dedicated to win condition checking allows easy scaling and independent updates without affecting other game components.

❓ scaling

advanced

Handling Win Condition Checks at Scale

In a system supporting thousands of concurrent games, what is the best approach to efficiently perform win condition checks?

A Distribute win condition checks across multiple worker nodes using event-driven architecture.

B Batch process win condition checks periodically for all games in a queue.

C Perform win condition checks synchronously immediately after each move on the main game server thread.

D Let clients perform win condition checks and report results to the server.

💡 Hint

Think about load distribution and responsiveness for many simultaneous games.

Using multiple worker nodes with event-driven triggers allows parallel processing and reduces bottlenecks, improving scalability and responsiveness.

❓ tradeoff

advanced

Tradeoffs in Win Condition Checking Frequency

What is a key tradeoff when choosing to check win conditions after every move versus checking periodically in batches?

A Checking after every move requires more complex synchronization mechanisms.

B Checking after every move increases responsiveness but may increase computational load.

C Batch checking guarantees immediate win detection but uses more memory.

D Batch checking reduces computational load but may delay detecting a winner.

💡 Hint

Consider responsiveness versus resource usage.

Checking win conditions after every move ensures immediate detection but can increase CPU usage, while batch checking saves resources but delays detection.

❓ estimation

expert

Estimating Capacity for Win Condition Checking Service

A win condition checking service processes 10,000 game state updates per second. Each check takes 5 milliseconds of CPU time. How many CPU cores are needed to handle this load without delay, assuming 100% CPU utilization per core?

A 2 cores

B 500 cores

C 50 cores

D 200 cores

💡 Hint

Calculate total CPU time needed per second and divide by CPU time per core.

Each check takes 5 ms, so 10,000 checks need 50,000 ms CPU time per second, which is 50 seconds of CPU time per second. Dividing by 1 second per core means 50 cores are needed.