February Challenge 2016
Chef and Strange Operations, Devu and a light discussion, Rectangles of Love, Chef-Detective, Matrix Maximum Sum, Sereja and Two Lines
March Challenge 2016
Chef And Special Dishes, Parity tree, maximize the sum, Floor Distribution, Palindromic substrings, Chef And Hungry Birds, Sereja and Two Strings 2
July Challenge 2016
Andrash and Stipendium, Chef and Segments, Chef and Tetris, Chef and special numbers, Evaluate the polynomial, Chef and Robots Competition, Chefland and Electricity, Defend the Recipe
November Challenge 2017
Product on the segment by modulo , Villages and Tribes, Periodic Palindrome Construction, Lovers Gift, Chef and Subarray Queries, Polynomials, Chef Hates Palindromes, Chef goes Left Right Left
June Challenge 2018 Division 1
Binary Board, Archi and Tree, Expected Buildings, Ways to Work, Vision, Two Flowers
February Challenge 2019 Division 1
Manhattan Rectangle, Guess It Right, Chef and Secret Ingredients, Xor Decomposition, Yet Another Tree Problem, (Challenge) Chef with Orchestra in the Kitchen, Art of Balance, Maximize the Tax
