August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Palindromic Game, Greedy Candidates
September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Little Chef and Sums
October Challenge 2017
Counter Test For CHEFSUM, A Balanced Contest, Max Mex, Chef and a great voluntary Program
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
August Cook-Off 2017
Real obtuse, From heaven to earth
January Challenge 2018
K-Concatenation, Partition the numbers, Maximum Score, Rectangle
March Challenge 2018 DIV 2
Embedding a Tree (Challenge), Minion Chef and Bananas, Minions and Voting, Chef and Glove, Mix the Colors, A Big Sale, Chef and Easy Problem
January Challenge 2019 Division 2
Different Neighbours, Lucky Number Game, Distinct Pairs, Chef and Modulo Game, Fancy Quotes, A Pizza Slice
India