September Challenge 2016
Faded Palindromes, Chef and calculation, Chef and digits of a number
June Challenge 2017
Triplets, Pairwise union of sets, Xenny and Coin Rankings, Chef and the Feast, Cloning, A Good Set, Chef and Prime Queries
July Challenge 2017
Chef and Sign Sequences, Pishty and tree, Whats in the Name, Calculator , IPC Trainers
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Palindromic Game, Greedy Candidates
Belarus