September Challenge 2019 Division 2
Chef and Interesting Subsequences , Easy Fibonacci
October Challenge 2019 Division 2
Missing Number, Bacterial Reproduction, Chef and Maximum Star Value, Array Modification, (Challenge) Maximizing LIS, Operations on a Matrix, Phone Prices, Even Edges
November Challenge 2019 Division 2
Hard Sequence, (Challenge) Coloring Triangulations, Weapon Value, Physical Exercise
November Cook-Off 2019 Division 2
The Biggest Restaurant, Signature, Chef Diet
December Challenge 2019 Division 1
Addition, (Challenge) Cubical Virus, Sticky Notes, Binary XOR, Chefina and Ranges, Test Generation
January Challenge 2020 Division 1
(Challenge) Building Anthills, Chefland Army, English, Chefina and Prefix Suffix Sums, Doofish Matrix, Doraemon, Chef and Dynamo
February Challenge 2020 Division 1
Chef and Railway Stations, Expected Change, No Change Required, (Challenge) Raisins, Long Contest and Cook Off Overlaps
March Challenge 2020 Division 1
Chef and DAG, Lasers Everywhere, Lasers Everywhere Alternative, (Challenge) 300 IQ Ants
Serbia