Online Judege Demo. Currently support Python and Java.

Your server has received a package of N incoming requests. Handling the K-th request (for K from 0 t

Design a data structure to return the next word in the dictionary...

Given two lists of intervals, each interval denoted as [start, end], find the intersection (overlapp

Find the longest diameter of a m-ary tree.

Given an undirected graph, find out all the vertices when removed will make the graph disconnec

Given a 2D grid, each cell is either a zombie or a human. Zombies can turn adjacent (up/down/left/ri

Find critical connections in a data center...

Your server has received a package of N incoming requests. Handling the K-th request (for K from 0 t

Given an array of integers representing the value of coupons, return the minimum number of consecuti

Given a string str and an integer k, you need to rearrange the string in a way that the same charact

Implement the following class to keep track of the first unique number in a data stream.

Given the bank currency exchange rate table, find out the best currency exchange rate from currency

Given the bank currency exchange rate table, find out if it’s possible to exchange from currency .

Given a two 2D integer array, find the max score of a path from the upper left corner to bottom righ