Affirm Interview Questions

#1. Shortest Uncommon Substring in an Array

ArraysStringsTwo PointersSliding Windows

Find the shortest string that is not a substring of any string within a given array of strings. Return this shortest uncommon substring.

This question is very likely to be asked in your Affirm interview

Insert Delete GetRandom O(1)

Design a data structure that supports insertion, deletion, and random element retrieval, all in constant time on average. You'll need to handle edge cases carefully to achieve O(1) complexity.

ArraysHash Table

Very likely

If you have a Affirm interview, it's very likely that you will get this question

#2. Insert Delete GetRandom O(1)

This question is very likely to be asked in your Affirm interview

Design a data structure that supports insertion, deletion, and random element retrieval, all in constant time on average. You'll need to handle edge cases carefully to achieve O(1) complexity.

ArraysHash Table

Group Anagrams

Given a list of words, group together all the anagrams. Anagrams are words that contain the same letters rearranged.

ArraysStrings

Somewhat likely

If you have a Affirm interview, you might get this question

#3. Group Anagrams

This question is somewhat likely to be asked in your Affirm interview

Given a list of words, group together all the anagrams. Anagrams are words that contain the same letters rearranged.

ArraysStrings

Parse Lisp Expression

You're given a Lisp-like expression string. Your task is to evaluate it and return the resulting integer value, following the specific rules of the expression's syntax and scope.

RecursionStrings

Somewhat likely

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#4. Parse Lisp Expression

This question is somewhat likely to be asked in your Affirm interview

You're given a Lisp-like expression string. Your task is to evaluate it and return the resulting integer value, following the specific rules of the expression's syntax and scope.

RecursionStrings

Design Hit Counter

Design a hit counter that records hits and retrieves the number of hits in the past 5 minutes. You need to implement methods to record a hit and get the total hits in a sliding window.

ArraysTwo PointersSliding Windows

If you have a Affirm interview, it's unlikely that you will get this question

#5. Design Hit Counter

ArraysTwo PointersSliding Windows

Design a hit counter that records hits and retrieves the number of hits in the past 5 minutes. You need to implement methods to record a hit and get the total hits in a sliding window.

This question is not likely to be asked in your Affirm interview

String Compression

Compress a given string by replacing consecutive repeating characters with the character followed by the count of repetitions. If the compressed string isn't shorter, return the original.

ArraysTwo PointersStrings

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#6. String Compression

ArraysTwo PointersStrings

Compress a given string by replacing consecutive repeating characters with the character followed by the count of repetitions. If the compressed string isn't shorter, return the original.

This question is not likely to be asked in your Affirm interview

Insert Delete GetRandom O(1) - Duplicates allowed

Design a data structure that supports insert, delete, and getRandom operations, all in constant time, even when duplicate numbers are allowed. The getRandom method should return a random element from the collection with equal probability.

ArraysHash TableDesign

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#7. Insert Delete GetRandom O(1) - Duplicates allowed

This question is not likely to be asked in your Affirm interview

ArraysHash TableDesign

Valid Anagram

Determine if two strings are anagrams of each other, meaning they contain the same characters in a different order. You need to check if one string can be rearranged to form the other.

StringsArrays

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Easy

#8. Valid Anagram

Easy

Determine if two strings are anagrams of each other, meaning they contain the same characters in a different order. You need to check if one string can be rearranged to form the other.

StringsArrays

This question is not likely to be asked in your Affirm interview

Coin Change

Given a set of coin denominations and a target amount, find the minimum number of coins needed to reach that amount. You can assume you have an unlimited supply of each coin type.

ArraysDynamic Programming

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#9. Coin Change

ArraysDynamic Programming

Given a set of coin denominations and a target amount, find the minimum number of coins needed to reach that amount. You can assume you have an unlimited supply of each coin type.

This question is not likely to be asked in your Affirm interview

String Compression III

You are given a string and a budget for removing characters. Your goal is to compress the string as much as possible after removing at most k characters. Find the length of the shortest possible compressed string.

Strings

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#10. String Compression III