Duolingo new grad 上门

面试日期 11/20/2019

OA hackerrank:
Q1 - https://leetcode.com/problems/find-peak-element/
Q2 - https://leetcode.com/problems/meeting-rooms-ii [a variant of this]

店面:
Write methods to encrypt and decrypt a word.

key = {‘a’: ‘bc’, ‘d’:‘cd’, ‘e’:‘bc’}
encrypt(‘aaaaa’) -> ‘bcbcbcbcbc’
decrypt(‘bcbc’) -> [‘aa’, ‘ae’, ‘ea’, ‘ee’]

上门在 Pittsburg
第一轮: https://leetcode.com/problems/range-sum-query-2d-immutable/
第二轮: https://leetcode.com/problems/longest-increasing-path-in-a-matrix/
第三轮: Given their codebase, find bugs and add new features such word sorting, code cleaning etc.
第四轮: HR round, questions about duolingo