July Challenge 2016
Chefland and Electricity, Andrash and Stipendium
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, 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 a great voluntary Program, A Balanced Contest, Counter Test For CHEFSUM, Max Mex, Chef and Cycled Cycles, Chef and Magic Arrays
November Challenge 2017
Product on the segment by modulo , Chef Hates Palindromes, Chef and Subarray Queries, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
Vietnam