September Challenge 2016
Chef and digits of a number, Faded Palindromes, Chef and calculation
October Cook-Off 2016
Watson asks Does Permutation Exist
February Challenge 2017
Chef and His Apartment Dues
March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number, Bandwidth of a matrix
January Cook-Off 2017
Digit Longest Increasing Subsequences 2
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
Chef and a great voluntary Program, Max Mex, A Balanced Contest
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