September Challenge 2016
Chef and digits of a number, Faded Palindromes, Chef and calculation
January Challenge 2017
Capital Movement, Cats and Dogs, Reservior
February Challenge 2017
Chef and Triangles, Chef and His Apartment Dues
March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number
April Challenge 2017
Bear and Row 01, Similar Dishes, Bear and Clique Distances, Dish Of Life
May Challenge 2017
Chef and his daily routine, Courses in an university, Blocked websites, Median of adjacent maximum numbers
June Challenge 2017
A Good Set, Chef and the Feast, Xenny and Coin Rankings, Triplets, Pairwise union of sets
July Challenge 2017
Chef and Sign Sequences, IPC Trainers, Whats in the Name, Calculator
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Palindromic Game, Greedy Candidates
September Challenge 2017
Sereja and Commands, Chef and Pick Digit, Minimum Good Permutation, Fill The Matrix, Little Chef and Sums
October Challenge 2017
Chef and Cycled Cycles, A Balanced Contest, Counter Test For CHEFSUM, Max Mex, Chef and a great voluntary Program
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, Partition the numbers
April Challenge 2019 Division 1
Playing with Numbers, Subtree Removal
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