June Challenge 2017
Chef and Prime Queries, A Good Set, Xenny and Coin Rankings, Triplets, Pairwise union of sets
October Challenge 2017
Max Mex, A Balanced Contest
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging
February Challenge 2018
Chef and odd queries, Permutation and Palindrome, Chef And His Characters
May Challenge 2018 Division 2
S-T Mincut, Mighty Friend, Change the Signs, Minimum Deletions, Xor Again, Fake Binary Search, Dibs on Fibs
April Cook-Off 2019 Division 1
Random Game, Pied Piper vs Hooli, Mystery Tree
Iran