September Challenge 2016
Chef and digits of a number, Faded Palindromes, Chef and calculation
February Challenge 2017
Chef and His Apartment Dues
March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number
April Challenge 2017
Dish Of Life, Bear and Row 01, Bear and Clique Distances, Similar Dishes
May Challenge 2017
Chef and his daily routine, Courses in an university, Blocked websites, Median of adjacent maximum numbers
June Challenge 2017
Pairwise union of sets, Triplets, Chef and the Feast, A Good Set, Xenny and Coin Rankings
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Greedy Candidates
September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Little Chef and Sums
October Challenge 2017
Max Mex, Counter Test For CHEFSUM, A Balanced Contest
September Lunchtime 2017
Chef and Cook-Off Contests
January Challenge 2018
K-Concatenation, Rectangle, Maximum Score
January Lunchtime 2018
Chef and Game with Sequence
February Challenge 2019 Division 2
Chef and Magical Jars, Chef and Secret Ingredients, Appy and Contest, Deputy Chef
October Challenge 2019 Division 2
Missing Number, Chef and Maximum Star Value, Operations on a Matrix
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