August Long Challenge 2017
Chef And Fibonacci Array, Chef and Mover, Palindromic Game, Greedy Candidates, Chef and Rainbow Array
September Challenge 2017
Little Chef and Sums, Fill The Matrix, Minimum Good Permutation, Chef and Pick Digit, Sereja and Commands
October Challenge 2017
Chef and Magic Arrays, Chef and a great voluntary Program, Max Mex, Counter Test For CHEFSUM, A Balanced Contest
December Challenge 2017
Total Diamonds, Chef and Hamming Distance of arrays, Red and blue points, Penalty Shoot-out, Chef And Easy Xor Queries, Chef And his Cake, Chef and Universe
July Cook-Off 2017
Chang and Bitwise OR, Chang and the Perfect Function
September Cook-Off 2017
Infinite OR Game, Statistics Construction, Subsequence Equality
December Cook-Off 2017
Beautiful Array, Football Match
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging
Ukraine