January Challenge 2019 Division 2
Different Neighbours, Yet Another Problem About Sequences, A Pizza Slice, (Challenge) Chef and Matching Game, Fancy Quotes, Distinct Pairs, Lucky Number Game, Chef and Modulo Game
December Challenge 2019 Division 2
Chefina and Ranges, Plus Multiply, Binary XOR, Easy Subsequence Selection, Sticky Notes, That Is My Score!, Addition
January Challenge 2020 Division 1
Chef and Dynamo, (Challenge) Building Anthills, Chefland Army, Army of Me, English, Chefina and Prefix Suffix Sums, Doofish Matrix, Doraemon
February Challenge 2020 Division 1
Long Contest and Cook Off Overlaps, (Challenge) Raisins, Chef and Gordon Ramsay 2, No Change Required, Expected Change, Chef and Railway Stations, Balancing Network Revisited
March Challenge 2020 Division 1
Inverse of a Function, Egg-free DAG, Good Subsequences, (Challenge) 300 IQ Ants, Lasers Everywhere Alternative, Lasers Everywhere, Winning Ways 2, Break, Chef and DAG
April Challenge 2020 Division 1
Squared Subsequences, Leaked Answers (Challenge), Line Line Line Graph, A Leisurely Journey, Factor Tree, Ready Bitwise, Perfect Power Divisors, Strange Number
June Challenge 2020 Division 1
The Tom and Jerry Game!, Operations on a Tuple, The Delicious Cake, Convenient Airports, Guessing Game, Perfect Partitions, Covid Sampling (Challenge), Danya and Different Values
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