Amazon SDE OA Simulation

Adding 4 votes at once keeps only the last

tallyVotes(votes) adds up every vote. The votes are counted at the same time with Promise.all. Example: await tallyVotes([1, 2, 3, 4]) → 10.

Async sum gives "[object Promise]3"

sumAsync(nums) adds up values that are fetched with an async function. Example: await sumAsync([1, 2, 3]) → 6.

Doubling with forEach returns an empty list

doubleAll(nums) doubles every number with fetchDouble, which takes a moment, and returns the results. Example: await doubleAll([1, 2, 3]) → [2, 4, 6].

Word lengths come back as promises, not numbers

wordLengths(words) returns the length of each word. Example: await wordLengths(["abc", "defg"]) → [3, 4].

Total shows "[object Promise]" instead of 6

sumDelayed(nums) adds up numbers that each arrive after a short delay. Example: await sumDelayed([1, 2, 3]) → 6.

Cached loader runs 3 times instead of once

countLoads(n) calls a cached loader n times at once and returns how many times the slow load really ran. It should always be 1. Example: await countLoads(3) → 1.

Counter method crashes inside forEach

countAll(items) counts the items using a Counter object. Example: countAll([1, 2, 3]) → 3.

AI Attempt: The English List

An AI assistant wrote formatNames(names), which turns a list into English, like ["A", "B", "C"] → "A, B and C". It must not change the list it is given. test_format checks that. Example: test_format(["Alice", "Bob", "Charlie"]) → "Alice, Bob and Charlie".

Page 1 shows the second page of items

pageItems(items, page, size) returns one page of items. Pages start at 1. Example: pageItems([1, 2, 3, 4, 5, 6], 1, 3) → [1, 2, 3].

Best window of 2 misses the last pair

max_window_sum(nums, k) returns the biggest sum of k numbers in a row. Example: max_window_sum([1, 2, 3, 10], 2) → 13 (3 + 10).

Binary search can't find the last item

binary_search(nums, target) returns the index of target in a sorted list, or -1 if it is not there. Example: binary_search([1, 3, 5, 7, 9], 9) → 4.

A reading of 0 degrees counts as missing

describe_temp(readings, station) returns "recorded" when the station sent any reading, including 0 degrees, and "missing" when it sent none. Example: describe_temp({"north": 0}, "north") → "recorded".

AI Attempt: FizzBuzz never says FizzBuzz

An AI assistant wrote this FizzBuzz. fizzbuzz(n) returns "Fizz" for multiples of 3, "Buzz" for multiples of 5, "FizzBuzz" for multiples of both, and otherwise the number as text. Example: fizzbuzz(15) → "FizzBuzz".

AI Attempt: The anagram checker

An AI assistant wrote this for a classic interview question. is_anagram(a, b) returns True when both words use the same letters, the same number of times. Example: is_anagram("listen", "silent") → True, is_anagram("aab", "abb") → False.

AI Attempt: Remove all occurrences

An AI assistant wrote this for a classic interview question. removeAll(arr, item) removes every copy of item from the array. Example: removeAll([1, 2, 2, 3], 2) → [1, 3].

Word count says 3 for "hello world"

count_words(text) counts the words, however many spaces are between them. Example: count_words("hello world") → 2.

Age is a year too high before the birthday

age_on(birth_iso, today_iso) returns how old someone is on a given date. Example: age_on("2000-12-25", "2024-06-01") → 23.

Two shoppers end up with the same basket

make_baskets(first, second) puts each item in its own new basket. Example: make_baskets("apple", "bread") → [["apple"], ["bread"]].