Given two arrays A and B of equal size, the advantage of A with respect to B is the number of indices i for which A[i] > B[i].

Given an integer array arr, and an integer target, return the number of tuples i, j, k such that i < j < k and arr[i] + arr[j] + arr[k] == target.

Given a wordlist, we want to implement a spellchecker that converts a query word into a correct word.

Starting with a positive integer N, we reorder the digits in any order (including the original order) such that the leading digit is not zero.

Implement the UndergroundSystem class:

There are N rooms and you start in room 0.

Given an integer array nums, return the length of the longest wiggle sequence.

Given the radius and x-y positions of the center of a circle, write a function randPoint which generates a uniform random point in the circle.

You are given an array prices where prices[i] is the price of a given stock on the ith day, and an integer fee representing a transaction fee.

Note: This is a companion problem to the System Design problem: Design TinyURL.