February Challenge 2017
Most Frequent Element, Chef and His Apartment Dues
March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number, Bandwidth of a matrix
May Challenge 2017
Chef and Sub Array , Chef and his daily routine, Courses in an university, Median of adjacent maximum numbers
June Challenge 2017
Pairwise union of sets, Triplets, Xenny and Coin Rankings, Chef and the Feast, A Good Set, Chef and Prime Queries
July Challenge 2017
Chef and Sign Sequences, Tree Expectancy, Whats in the Name, Calculator , IPC Trainers
August Long Challenge 2017
Chef and Rainbow Array, Chef And Fibonacci Array, Chef and Mover, Palindromic Game, Greedy Candidates
September Challenge 2017
Little Chef and Sums, Fill The Matrix, Weasel does Xor on Tree, Chef and Pick Digit, Sereja and Commands, Minimum Good Permutation
October Challenge 2017
Chef and a great voluntary Program, Max Mex, Counter Test For CHEFSUM, A Balanced Contest
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
September Cook-Off 2017
Infinite OR Game, Statistics Construction, Subsequence Equality
November Cook-Off 2017
Random Pair, Skiing, Online Chess
September Lunchtime 2017
Chef and Dice, Chef and Cook-Off Contests
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging, Partition the numbers
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