Robina Li

Given an array of meeting time intervals intervals where intervals[i] = [starti, endi], return the minimum number of conference rooms required.

Given two binary strings a and b, return their sum as a binary string.

Given two 1d vectors, implement an iterator to return their elements alternately.

Design a Skiplist without using any built-in libraries.

Given an array nums with n objects colored red, white, or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order...

Given the coordinates of four points in 2D space p1, p2, p3, and p4, return true if the four points construct a square.

Design a data structure that follows the constraints of a Least Recently Used (LRU) cache.

Design a data structure that follows the constraints of a Least Recently Used (LRU) cache.

[Medium] Round Trip Ticket Cost Minimization

You have planned some train traveling one year in advance. The days of the year in which you will travel are given as an integer array days. Each day is...