June Challenge 2017
Xenny and Coin Rankings, A Good Set
October Challenge 2017
Max Mex, A Balanced Contest
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
December Challenge 2017
Total Diamonds, Chef And his Cake, Chef And Easy Xor Queries, Penalty Shoot-out, Chef and Hamming Distance of arrays
November Cook-Off 2017
Skiing, Online Chess, Random Pair
December Cook-Off 2017
Beautiful Array, Football Match
February Challenge 2018
Chef And His Characters, Chef And The Patents, Car-pal Tunnel, Permutation and Palindrome
April Challenge 2018 Division 2
Workers, Average of Pairs, Highway Crossing, Weight of Numbers, Count Good Prefixes
June Challenge 2018 Division 2
Binary Shuffle, Naive Chef
December Challenge 2018 Division 2
Chef and Interactive Contests, Chef and An Ideal Problem
November Challenge 2018 Division 2
Chef and Happiness, Chef and Difficult Contests, Chef and Ridges
October Challenge 2018 Division 1
Appy and Balloons , Minimize Digitsum, Byte to Bit
June Lunchtime 2018 Division 2
Summary Power, Counting Pretty Numbers
January Challenge 2019 Division 2
Yet Another Problem About Sequences, A Pizza Slice, Fancy Quotes, Chef and Modulo Game, Distinct Pairs, Lucky Number Game, Different Neighbours
February Challenge 2019 Division 1
Manhattan Rectangle, Guess It Right, Chef and Secret Ingredients, Art of Balance
India