Group Anagrams
A medium-tier problem at 71% community acceptance, tagged with Array, Hash Table, String. Reported in interviews at BP and 79 others.
Group Anagrams is a medium-difficulty array problem that 80+ companies ask, including Workday, Paycom, and Dell. You get a list of strings and need to group anagrams together. The 70% acceptance rate is deceptive; most failures come from candidates who nail the logic but pick the wrong hash key or fail to sort within groups. The trick is brutal if you haven't seen it before, and the interview moves fast. If this problem hits your live assessment and you blank on the optimal key structure, StealthCoder runs invisibly during screen share and surfaces a working solution in seconds.
Companies that ask "Group Anagrams"
Group Anagrams is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know.
Get StealthCoderThe naive approach sorts each string individually and uses that as a hash key, which works but wastes time on repeated sorts. The optimal pattern is to sort each word once, use the sorted form as the dictionary key, and append the original string to its anagram bucket. Common failure points: forgetting that anagrams have identical sorted characters, using a set instead of a list (you need to return groups, not uniqueness), or trying to compare strings pairwise (O(n^2) horror). The problem tests whether you recognize that sorting is a canonical form for anagram equivalence. It requires Array, Hash Table, String, and Sorting skills in tandem. If you haven't drilled this specific pattern, StealthCoder is the hedge that keeps you from burning 20 minutes on a botched attempt.
Pattern tags
You know the problem.
Make sure you actually pass it.
Group Anagrams recycles across companies for a reason. It's medium-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Group Anagrams interview FAQ
Why is sorting the string the right key, not character counts?+
Both work. Sorting is simpler to implement and understand in an interview. Character count (e.g., 'a:1,b:2') is faster but requires tuple or string construction. Sorting a short string is negligible overhead. Pick sorting unless the interviewer explicitly asks for optimization.
Does Group Anagrams still come up at big tech companies?+
Yes. 80 companies on record ask it, from Workday to Nielsen to Dell. It's a stable problem that tests fundamental data structure intuition. Not as flashy as graph problems, but it appears consistently in non-FAANG interviews and second-round OAs.
What if I use a set to deduplicate, then return groups?+
You'll lose the original strings. Anagram grouping requires returning the full strings in their original form, not just unique buckets. You need a dict (hash table) that maps the sorted key to a list of original strings, then return the lists.
Is there a way to avoid sorting each string?+
Sorting is O(k log k) per string (k = string length), which is optimal for canonicalizing anagrams in a single pass. Character count loops are O(k) and slightly faster in practice, but the code is messier. Sorting is the interview-friendly choice.
How does Group Anagrams relate to the Hash Table and Sorting topics?+
Hash Table is the container; Sorting is the key generation strategy. You sort to create a unique, comparable anagram signature, then hash it for O(1) bucket lookup. Mastering this pattern teaches you when to use sorting as a preprocessing step before hashing.
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