Question

PhonePe | Interview Experiences | SDE | Set-10

Answer 1

Coding Round: Design and code a Queue Service, allowing multiple subscribers on a topic. Each consumer can have multiple pollers – implement parallel polling using sub queues, assuming that producer can have ordering key used to send messages to the same sub queue. — Code interfaces : (subscribe, publish, consume), allow extension for multiple pollers (initially taking just one poller).

Ensure what is expected from queue: Msg ordering, consistency, availability.

DS, Algo, PS Round:  Beakers arranged vertically, and number of beakers increase by 1 at each level

        1

      2  3

   4   5   6

 

Given k is capacity of each beaker. When x ml of water is put, how much will flow to nth beaker.

Solve using recursion.

Design Round: 

1. Producer, Consumer for posts with Read count, write count limit per user topic, ensure fast reads (scale) – cache to be used,  distributed to allow read/write to scale.
2. Distributed cache  – how is it distributed
3. Check if a given expression is a tautology – always true – alphabets a-z are present in the expression

(a&&b) || !(a&&b)

• solve using stack, check priority of operator