March Challenge 2015
Chef and Notebooks, Count Substrings, Matrix, Sign Wave, Sereja and Random Array, Devu and his Class
April Challenge 2015
Devus and their voting system, Chef and Piano Scales, Inversion sorting, Broken Telephone, Chef and Interview, Chef and Array, Count Sequences
May Challenge 2015
Devu and his three Hands, Devu and binary String, Chef and Prime Divisors, Set Difference , Chef and new recipe, Chef and Cake
June Challenge 2015
Chef and Polygons, Chef and Memory Limit, Steady tables, Chef and His Friend
September Challenge 2015
Chain of Doughnuts, Count Steps in Matrix, Bank robbery, Lighthouses
March Cook-Off 2015
How to Minimize a String, How to Repaint a Fence
September Mega Cook-Off 2015
Stacks, Super Numbers, Forgotten Language, Reign 2
August Long Challenge 2017
Chef and Rainbow Array, Chef And Fibonacci Array, Chef and Mover, Hill Jumping, Palindromic Game, Greedy Candidates, Strings and Graphs
August Cook-Off 2017
Matrix and Chef, Real obtuse, From heaven to earth
Poland