Assume we have a Node class with: int val Node right Node left Input: binary tree of ints (you’ll be given root node) Return the boundary traversal of t…

Given a string s consisting of lowercase English characters, determine if you can make it a palindrome by removing at most one letter. Example 1: Input:…

Given a social network, a start person, and an end person, find the minimum number of steps from person A to person B. Example: 1 -> 2 -> 5 | | |…

A multiset (also known as a bag) is a mutable, unordered collection of distinct objects that may appear more than once in the collection. Implement a mu…

Write a function that calculates the dot product of two vectors. 96% of vector components are zero. What is a good data structure for v1 , v2 so that yo…

Given a sequence of integers and an integer total target, return whether a continuous sequence of integers sums up to target. Example: [1, 3, 1, 4, 23],…

Find all palindromes in a string. This problem asks you to find all palindromic substrings in a string. A common and reliable approach is center expansi…

Q2: Print missing numbers Input: [2, 4, 7, 13, 20] Output: "0,1,3,5,6,8-12,14-19,21-99" Given a sorted list of numbers, print all missing numb…

Given a string containing characters ( and ) , find the length of the longest valid parentheses substring. This problem asks for the length of the longe…

Given an array of integers, return the index of one of the largest elements, chosen uniformly at random. Example: index: 0 1 2 3 4 5 6 array: [5, 3, 6,…

Given an array of integers nums and an integer k , return the total number of subarrays whose sum equals k . A subarray is a contiguous non-empty sequen…

Given a string containing uppercase characters A-Z, remove pairs of adjacent characters if they are consecutive characters in the alphabet (for example,…

The input is a string containing open and close parentheses. Find the minimum number of parentheses that need to be added in order to balance the input…

Given a grid of land heights. For example: start 6 5 4 5 5 4 2 5 1 1 5 5 2 1 5 2 3 2 4 4 5 4 5 5 6 end The upper-left corner is the start cell, and the…

Given an integer, swap at most one pair of digits to make the largest possible integer. Example: 43183 -> 83143 Swap 4 and 8. The key idea is to maximiz…

Write a query to find the total value of sales and the number of unique paying customers, grouped and sorted in descending order by payment type. Existi…

Write a function that returns the smallest nonnegative number which can be generated by using all the digits with odd values of a given number. Example:…

This set of SQL interview questions uses a bookstore database with the following tables: books , authors , transactions , and customers . books book_id…

Meta VO Interview Question: Carpooling Value Proposition, Metrics, and Data Model Design A ride-share service allows customers to use an app to request…

Given a binary tree (pointer to the root), a target node anywhere in the tree, and an integer value K , return a list of the values of all the nodes tha…