October Challenge 2019 Division 2
Missing Number, Bacterial Reproduction, Chef and Maximum Star Value, Array Modification, Operations on a Matrix, Phone Prices, Even Edges
December Challenge 2019 Division 2
Addition, That Is My Score!, (Challenge) Cubical Virus, Sticky Notes, Binomial Fever, Binary XOR, Plus Multiply, Chefina and Ranges, Easy Subsequence Selection
February Challenge 2020 Division 1
Long Contest and Cook Off Overlaps, Chef and Gordon Ramsay 2, No Change Required, Expected Change, Chef and Railway Stations
March Challenge 2020 Division 1
Chef and DAG, Winning Ways 2, Lasers Everywhere, Inverse of a Function, Lasers Everywhere Alternative, Egg-free DAG
April Challenge 2020 Division 1
Strange Number, Leaked Answers (Challenge), Factor Tree, Perfect Power Divisors, Squared Subsequences, Ready Bitwise
May Challenge 2020 Division 1
Buying a New String, Triple Sort, Binary Land, Not a Real World Problem, Chef and Rainbow Road, Chef and Bitwise Product
July Challenge 2020 Division 1
Missing a Point, Doctor Chef, Chef and Dragon Dens, Chefina and Swaps
November Challenge 2020 Division 1
Chef and the Combination Lock, Restore Sequence, Magical Candy Store, Scalar Product Tree, Unusual Queries
February Challenge 2021 Division 1
Team Name, Another Tree with Number Theory, Prime Game, Multiple Games, XOR Sums
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