July Challenge 2017
Chef and Sign Sequences, Calculator , Whats in the Name
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
November Challenge 2017
Chef goes Left Right Left, Villages and Tribes, Periodic Palindrome Construction
December Challenge 2017
Chef And his Cake, Penalty Shoot-out
August Cook-Off 2017
Real obtuse, From heaven to earth
February Challenge 2018
Chef And His Characters, Chef And The Patents, Permutation and Palindrome
May Challenge 2018 Division 2
Minimum Deletions, Xor Again
December Challenge 2018 Division 2
Max and Electrical Panel, Chef and An Ideal Problem, Chef and Interactive Contests, Chef and Interactive XOR
June Lunchtime 2018 Division 2
Summary Power, Counting Pretty Numbers
December Challenge 2019 Division 2
Plus Multiply, That Is My Score!
Indonesia