March Challenge 2017
Bear and Extra Number, Xenny and Alternating Tasks, Bandwidth of a matrix
May Challenge 2017
Chef and his daily routine, Courses in an university, Median of adjacent maximum numbers, Chef and Subsequences
June Challenge 2017
A Good Set, Chef and the Feast, Xenny and Coin Rankings, Triplets, Pairwise union of sets
September Challenge 2017
Little Chef and Sums, Minimum Good Permutation, Chef and Pick Digit, Sereja and Commands
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
December Cook-Off 2017
Beautiful Array, Football Match
December Lunchtime 2017
Days in Month, Strange Function
January Challenge 2018
Partition the numbers, String Merging, Maximum Score, K-Concatenation, Killjee and k-th letter , Rectangle
January Lunchtime 2018
Chef and Game with Sequence, Chef and Escaping from the Labyrinth
February Challenge 2018
Broken Clock, Chef And Land Labeling, Chef And His Characters, Chef And The Patents, Points Inside A Polygon, Car-pal Tunnel, (Challenge) Biased Committee, Permutation and Palindrome
June Challenge 2018 Division 1
Two Flowers, Ways to Work, Vision
February Challenge 2019 Division 1
Manhattan Rectangle, Guess It Right, Chef and Secret Ingredients, Xor Decomposition, Art of Balance, Maximize the Tax
May Challenge 2020 Division 1
Buying a New String, Triple Sort, Binary Land, Sorting Vases, Chef and Bitwise Product
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