September Challenge 2019 Division 2
Easy Fibonacci, Chef and Interesting Subsequences , Chef and Good Subsequences
October Challenge 2019 Division 2
Even Edges, Missing Number, Chef and Maximum Star Value, Array Modification, Operations on a Matrix, Phone Prices
November Challenge 2019 Division 2
Physical Exercise, Chef and Minimum Colouring, Weapon Value, Single Point of Failure, From Zero to Infinity, Smallest Beautiful Number, Hard Sequence
January Challenge 2020 Division 1
Chef and Dynamo, Chefina and Prefix Suffix Sums, Doraemon
April Challenge 2020 Division 1
Strange Number, Squared Subsequences
September Challenge 2020 Division 2
Chefina and Swap, A Problem on Sticks, Chef and Trump Cards, Find XOR, Ada Matrix, Coronavirus Spread 2
January Challenge 2021 Division 2
Expected Number of SCCs, Watching CPL, Fair Elections
February Challenge 2021 Division 2
Prime Game, Maximise Function
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