June Challenge 2019 Division 2
Chef and Proxy, Road Signs, Chef and Ingredients, Guddu on a Date
September Challenge 2019 Division 2
Chef and Good Subsequences, Easy Fibonacci, Biladerim Icin, Fuzzy Linear Combinations, Doofish Set, Chef Designed a Network, Chef and Interesting Subsequences
November Challenge 2019 Division 2
Physical Exercise, Hard Sequence, Weapon Value
December Challenge 2019 Division 2
Binary XOR, Addition, That Is My Score!, Easy Subsequence Selection, Plus Multiply, Chefina and Ranges
May Challenge 2020 Division 2
Triple Sort, Coronavirus Spread, Chef and Bitwise Product, Isolation Centers
November Challenge 2020 Division 1
Restore Sequence, Magical Candy Store
December Challenge 2020 Division 1
Even Pair Sum, String Operations, Hail XOR, Positive Prefixes
February Challenge 2021 Division 2
Frog Sort, Team Name, Prime Game, Maximise Function
March Challenge 2021 Division 2
Interesting XOR!, Dense Graph, College Life 4, Consecutive Adding, Paparazzi Gennady, Space Arrays, Wireless Electricity (Challenge), Maximum Topological Sort
April Challenge 2021 Division 2
Worthy Matrix, Boolean Game, Chef and Dice, Binary String MEX
May Challenge 2021 Division 2 (Rated)
Valid Paths, Tree House, King Killing, Xor Equality, Tic Tac Toe, Modular Equation
June Challenge 2021 Division 2 (Unrated)
Minimum Dual Area, Shortest Route, Bitwise Tuples, Bella ciao, Summer Heat, Minimum Subtree Cover
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