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Solve prefix, array, and string problems

Last updated: Apr 27, 2026

Quick Overview

This set of problems evaluates proficiency in string and array algorithm design—covering prefix search, subsequence matching, and maximal-area computation from bar heights—measuring competence in algorithmic thinking, data structure usage, and time/space efficiency.

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Solve prefix, array, and string problems

Apr 9, 2025, 12:00 AM

mediumMachine Learning EngineerOnsiteCoding & Algorithms

Practice Read

The interview included several coding problems:

First index matching a prefix : Given a sorted array of lowercase strings such as ["a", "apple", "appz", "b"] and a prefix such as "ap" , return the index of the first word that starts with the prefix. If no word matches, return -1 .
Maximum rectangle from bar heights : Given an array of non-negative integers representing adjacent bar heights, where each bar has width 1 , return the maximum rectangular area that can be formed using one or more consecutive bars.
Check ordered deletion match : Given two strings s and t , determine whether s can be formed by deleting some characters from t without changing the order of the remaining characters.