The math behind the coding challenge. · Problem statement Given an integer n, return the least number of perfect square numbers that sum to n. A perfect...

A simple example of dynamic programming · Problem statement The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence,...

Decoding Roman numbers · Problem statement Roman numerals are represented by seven symbols: I, V, X, L, C, D, and M. Symbol Value I 1 V...

Problem Statement Given an array of integers nums and an integer k, return the total number of continuous subarrays whose sum equals to k. Example...

Introduction to a mathematical Permutation · Problem statement You are given an integer array nums of length n where nums is a permutation of the numbers...

Problem statement Given a reference of a node in a connected undirected graph. Return a deep copy (clone) of the graph. Each node in the graph...