Robina Li

Difficulty: Medium Category: Design, Array, Matrix Companies: Amazon, Google, Microsoft, Facebook

Difficulty: Medium Category: Array, Matrix, DFS Companies: Amazon, Google, Microsoft

Difficulty: Medium Category: Tree, DFS, Binary Tree Companies: Amazon, Google, Facebook, Microsoft

Difficulty: Medium Category: Array, Hash Table, Heap, Bucket Sort, Quickselect Companies: Amazon, Google, Facebook, Microsoft, Apple

Difficulty: Medium Category: Array, Sorting, Heap, Quickselect Companies: Amazon, Google, Facebook, Microsoft

Difficulty: Easy Category: Array, Hash Table Companies: Amazon, Google, Microsoft

There are a total of numCourses courses you have to take, labeled from 0 to numCourses - 1. You are given an array prerequisites where prerequisites[i] = [ai, bi] indicates...

Given a reference of a node in a connected undirected graph.

You have a lock in front of you with 4 circular wheels. Each wheel has 10 slots: '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'. The wheels can...

Given the root of a binary tree, return the vertical order traversal of its nodes’ values. (i.e., from top to bottom, column by column).