June Challenge 2017
Chef and the Feast, A Good Set, Pairwise union of sets, Xenny and Coin Rankings
July Challenge 2017
Chef and Sign Sequences, Whats in the Name, Calculator , IPC Trainers
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Palindromic Game, Greedy Candidates, Strings and Graphs
October Challenge 2017
Max Mex, A Balanced Contest, Counter Test For CHEFSUM, Chef and a great voluntary Program
November Challenge 2017
Chef and Intersection Line, Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
August Cook-Off 2017
From heaven to earth, Real obtuse
October Cook-Off 2017
Chef and Employment Test, Chef and Weird Queries
August Lunchtime 2017
Mathison and the Dynamo shuffle, Mathison and pangrams
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging, Partition the numbers
February Challenge 2018
Chef And His Characters, Permutation and Palindrome, Car-pal Tunnel, Akanksha and End of Semester, Chef And The Patents
March Challenge 2021 Division 2
Interesting XOR!, Space Arrays
April Challenge 2021 Division 2
Worthy Matrix, Chef and Dice
May Challenge 2021 Division 2 (Rated)
Tree House, Xor Equality, Tic Tac Toe
India