June Challenge 2018 Division 2
Two Flowers, Vision, Sheokand and String, Naive Chef
September Challenge 2018 Division 2
AND Square Subsegments, Sasha and Photos, Magician versus Chef, War of XORs, Chef and Adventures, Table Game, Bad Shuffle
August Lunchtime 2019 Division 2
Destroy Cells, Chef Does Coke Yet Again
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
December Challenge 2019 Division 2
Addition, That Is My Score!, Easy Subsequence Selection, Plus Multiply, Chefina and Ranges, Binary XOR
February Challenge 2020 Division 1
Chef and Railway Stations, Expected Change, No Change Required, Chef and Gordon Ramsay 2, Long Contest and Cook Off Overlaps
April Challenge 2020 Division 1
Factor Tree, Leaked Answers (Challenge), Ready Bitwise, Perfect Power Divisors, Squared Subsequences, Strange Number
May Challenge 2020 Division 1
Buying a New String, Triple Sort, Chef and Bitwise Product
July Challenge 2020 Division 1
LCM Constraints, Chefina and Swaps, Chef and Dragon Dens, Missing a Point, Weird Product
August Challenge 2020 Division 1
Subsequence Frequency Counting, Smallest KMP, Chef and Wedding Arrangements
Vietnam