Top 50 frequency count Interview Questions

Determine whether two DELFI identifier strings are anagrams using character frequency counting.

Hash Tablesfrequency countStringsArcesiumPrutech SolutionsLam Research

Determine whether two lowercase strings are anagrams by comparing their character frequencies in linear time.

Hash Tablesfrequency countStringsWiproMedline IndustriesOneTrust

Count characters across multiple strings and return the most frequent one with deterministic tie-breaking.

aggregationfrequency countArraysCapgemini FSSBUCapgemini Government SolutionsIBS Software

Count item frequencies and use a min-heap to return the top k items efficiently from a massive dataset.

aggregationfrequency countData StructuresLyftTTescoWarner Bros. Discovery

Detect transaction indices whose values exceed a rolling sample-standard-deviation threshold using an O(n) sliding window.

streamingaggregationfrequency countTruistRyanTTangerine

Build each position's product excluding itself using prefix and suffix products in O(n) time.

Basic Algorithmsfrequency countArraysZillowAsana