September Challenge 2017
Minimum Good Permutation, Chef and Pick Digit, Little Chef and Sums
October Challenge 2017
Max Mex, Counter Test For CHEFSUM, A Balanced Contest
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
October Cook-Off 2017
Chef and Weird Queries, Chef and Employment Test
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging, Partition the numbers
February Challenge 2018
Permutation and Palindrome, (Challenge) Biased Committee, Car-pal Tunnel, Akanksha and End of Semester, Chef And The Patents, Chef And His Characters, Broken Clock, Points Inside A Polygon
March Challenge 2018 DIV 1
Chef and Easy Problem, Mix the Colors, Minions and Voting
April Challenge 2018 Division 1
Count Good Prefixes, Highway Crossing, Cutting Plants, Chef and Array (Challenge)
May Challenge 2018 Division 1
Change the Signs, Not a Convex Hull (Challenge), Fake Binary Search, Dibs on Fibs
Dementia (Rated for Division 2)
Strings, Chef and Replication
January Challenge 2020 Division 1
Chef and Dynamo, Doraemon, Chefina and Prefix Suffix Sums
India