September Challenge 2016
Dividing Machine, Chef and digits of a number, Faded Palindromes, JosephLand, Chef and calculation, Chef and Friends
October Challenge 2016
Sereja and Stones, Chef and Keyboard, Big Queries, Fenwick Iterations, Chef and Three Dogs, Chef and Two String, Bear and Shuffled Points
November Challenge 2016
Kirito in Memeland, Task for Alexey, Chef and squares, Urban Development, Friends Meeting, Count Permutations, Gift and Chef
June Challenge 2017
Xenny and Coin Rankings, Pairwise union of sets, Triplets, Chef and the Feast, Cloning, A Good Set, Euler Sum, Chef and Prime Queries
September Challenge 2017
Sereja and Commands, Chef and Pick Digit, Minimum Good Permutation, Fill The Matrix, Little Chef and Sums
Indonesia