September Challenge 2016
Faded Palindromes, Chef and digits of a number
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, (CH) Bear and Sorted Rows, Bandwidth of a matrix
January Cook-Off 2017
Digit Longest Increasing Subsequences 2
April Challenge 2017
Similar Dishes, Dish Of Life
June Challenge 2017
A Good Set, Xenny and Coin Rankings
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, Partition the numbers
January Lunchtime 2018
Chef and Game with Sequence
February Challenge 2018
Chef And His Characters, Chef And The Patents, Permutation and Palindrome
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