March Challenge 2017
Bear and Extra Number, Xenny and Alternating Tasks, Bandwidth of a matrix, (CH) Bear and Sorted Rows
April Challenge 2017
Bear and Row 01, Similar Dishes
May Challenge 2017
Chef and his daily routine, Courses in an university, Median of adjacent maximum numbers
June Challenge 2017
A Good Set, Chef and the Feast, Xenny and Coin Rankings, Pairwise union of sets
October Challenge 2017
A Balanced Contest, Max Mex
March Challenge 2018 DIV 2
A Big Sale, Mix the Colors, Chef and Glove
August Challenge 2019 Division 2
Zombie and the Caves, Football, Dilemma, Distribute Apples
April Challenge 2020 Division 2
Strange Number, Squared Subsequences, Ready Bitwise, Unit GCD, Sell All the Cars, Leaked Answers (Challenge), COVID Pandemic and Long Queue
May Challenge 2020 Division 2
Coronavirus Spread, Isolation Centers, Triple Sort
April Cook-Off 2020 Division 2
Matrix Decomposition, Lift Requests
March Lunchtime 2020 Division 2 (Unrated)
Chef Swaps Digits, Good Prefix
June Challenge 2020 Division 2
Even Matrix, The Tom and Jerry Game!, Chef and Icecream, Chef and String, Chef and Price Control
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