Roku Interview Questions

Design a data structure that acts as a Least Recently Used (LRU) cache. Implement methods to get and put key-value pairs, evicting the least recently used entry when the cache is full.

Find the k most frequent elements in a given array of numbers. Return the top k elements based on their frequency.

Find all starting indices of substring(s) in a given string that are formed by the concatenation of all words from a provided list, where each word must appear exactly once and without any intervening characters.

Find the maximum value within each sliding window of a given size as it moves across an array.

Given an absolute file path (Unix style), simplify it by resolving redundant separators, directory names, and navigating back up the directory structure. Return the simplified canonical path.

Simulate multiplication of two non-negative integers represented as strings. Return the product, also represented as a string.

Determine if a string containing parentheses and asterisks is a valid parenthesis string. The asterisk can represent a left parenthesis, a right parenthesis, or an empty string.

Given four numbers, determine if you can use the operations +, -, *, and / to reach the value 24. Each number must be used exactly once.

You are given a grid with keys and locks. Find the shortest path to collect all the keys, where each key unlocks a corresponding lock.

Simulate backspace operations on two strings and determine if the resulting strings are equal. Effectively, you need to compare strings after processing backspace characters.

Determine if a string is a palindrome after removing at most one character. Consider both left and right removals when checking for palindrome validity.

Distribute candies to children standing in a line such that each child with a higher rating gets more candies than their neighbors. Find the minimum number of candies needed.

You're given a list of asteroids, each with a size and direction (positive is right, negative is left). Figure out which asteroids will survive after all collisions happen.

Find the three numbers in a given array whose product is maximum. Return the maximum product possible from any three numbers in the array.

The problem involves decoding a string that follows a specific encoding rule: k[encoded_string], where the encoded_string inside the square brackets is repeated exactly k times. Your task is to decode the string and return the decoded string.

Find the longest subarray containing only 1s, where you are allowed to flip up to k 0s to 1s. Return the maximum length of such a subarray.