Mini OA: rate limiter
Allow at most limit requests per user inside the last window seconds. Return one boolean per request.
What you’ll practice
This Level 3 exercise focuses on deque + defaultdict in the Collections curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.
Relevant Python reference: collections.defaultdict, collections.deque.
Sample Test Cases
allow_requests([('a',1),('a',2),('a',3)], limit=2, window=5)[True,True,False]Further Reading
Reference Solution
Reveal Reference Solution
def allow_requests(requests: list[tuple[str,int]], limit: int, window: int) -> list[bool]: from collections import defaultdict, deque history = defaultdict(deque) result = [] for user, time in requests: queue = history[user] while queue and queue[0] <= time-window: queue.popleft() allowed = len(queue) < limit result.append(allowed) if allowed: queue.append(time) return resultPro Tips & Keyboard Shortcuts
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