Link to problem Problem Given a sentence text (A sentence is a string of space-separated words) in the following format: First letter is in upper case. Each word in text are separated by a ...

Link to problem Problem A wiggle sequence is a sequence where the differences between successive numbers strictly alternate between positive and negative. The first difference (if one exists) may...

Link to problem Problem There is an undirected tree with n nodes labeled from 0 to n - 1 and n - 1 edges. You are given a 2D integer array edges of length n - 1 where edges[i] = [ai, bi] indicat...

Link to problem Problem There is an integer array nums sorted in non-decreasing order (not necessarily with distinct values). Before being passed to your function, nums is rotated at an unknown ...

Link to problem Problem You are given an integer array arr of length n that represents a permutation of the integers in the range [0, n - 1]. We split arr into some number of chunks (i.e., parti...

Link to problem Problem You are given an integer n. There is an undirected graph with n nodes, numbered from 0 to n - 1. You are given a 2D integer array edges where edges[i] = [ai, bi] denotes t...

Link to problem Problem Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order. Solution I have two slightly different solutio...

Link to problem Problem A k x k magic square is a k x k grid filled with integers such that every row sum, every column sum, and both diagonal sums are all equal. The integers in the magic square...

Recently, a footage showing world first clear of The Omega Protocol using plugins that could zoom in sparked the discussion of the use of third party tools (again). The problem was solved by SE in ...

Last year, I went to Michigan to visit a friend during holiday season. But why not spending the time with my family? Well, plane ticket back to my hometown costs too much. And for the same reason, ...