Hackerearth Basic Programming Bit Manipulations Hihi and Crazy bits Mystery Subham and Binary Strings Monk and the box of cookies The Castle Gate Bit Flipping Game Lazy Panda Help your roommate Jarvis and Lone Integer Subset AND Flash vs Katmos Rajan and Odd frequency number MYSTERY Input / Output Anagrams Best Index Count Divisors E-Maze-In Factorial Find Product Palindromic String Prime numbers Roy and Profile Picture Seating Arrangements Toggle String Authors Alkesh Ghorpade