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fastprep / bank / stripe-q3 / P-201 - token-bucket rate limiterHOTseen 47x this week
Token-bucket rate limiterStripemedium12mdesign

Implement allow(ts) returning True if a request is permitted at unix ms ts for r req/s with burst up to b.

solution.pytests.txtnotes.mdpy 3.12 - 5.0ms
class RateLimiter:
    def __init__(self, r, b):
        self.r, self.b = r, b
        self.tokens, self.last = b, 0

    def allow(self, ts):
        # refill since last call
        self.tokens = min(self.b, self.tokens + (ts - self.last) * self.r)
        self.last = ts
        return self.tokens >= 1
passbasic_one_req_per_sec0.4ms
passburst_5_then_refill1.1ms
passmonotonic_timestamps0.9ms
passedge_ts_equal_last0.6ms
4 / 4 passed - 3.0ms total+ custom test
2,472
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241
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topics covered
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241 companies

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AAmazon
485problems
5 formatsAlgorithms
GGoogle
125problems
2 formatsAlgorithms
TTiktok
114problems
1 formatAlgorithms
MMicrosoft
93problems
2 formatsAlgorithms
IIBM
86problems
1 formatAlgorithms
UUber
75problems
3 formatsAlgorithms
SSalesforce
69problems
2 formatsAlgorithms
SSnowflake
63problems
2 formatsAlgorithms
AAtlassian
60problems
1 formatAlgorithms
SStripe
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2 formatsAlgorithms
OOpenAI
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3 formatsAlgorithms
GGoldman Sachs
42problems
3 formatsAlgorithms
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bank - filter2,472 -> 12
company
StripeDoorDashAirtable+238
stage
assessmentphoneonsitedesign
difficulty
easymediumhard
format
algorithmdatadesignproject
12 matchedfrom 2,472
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When tracked inboxes start seeing Stripe OAs land, the Q3 set surfaces to the top. You practice this quarter's questions, not the ones that were popular in 2019.

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signal -> bank - last 7 dayslive
Stripe+12.4%promoted Q3 set47 pr
DoorDash+8.1%added 4 new problems32 pr
Anthropic+6.2%new cohort opened18 pr
Airtable+3.0%refreshed test cases28 pr
Adobe-2.1%lowered priority22 pr
Teslafrozenarchived19 pr
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