January Challenge 2018
Maximum Score, Rectangle, Partition the numbers, K-Concatenation
January Cook-Off 2018
Multiple of 3, Survive in ChocoLand
February Challenge 2018
Car-pal Tunnel, Permutation and Palindrome, (Challenge) Biased Committee, Points Inside A Polygon, Chef and odd queries, Chef And The Patents, Chef And His Characters, Chef And Land Labeling, Lucas Theorem, Broken Clock
February Cook-Off 2018
Chef and Cook-Off, Chef and Tuples, Chef and Line
March Challenge 2018 DIV 1
Chef and Easy Problem, Chef and Gcd Queries, Mix the Colors
August Challenge 2018 Division 2
Modular GCD, Spell Bob, Sheokand and Number, Problem Sort, Princess and Dragons
October Challenge 2018 Division 1
Appy and Balloons , Minimize Digitsum
September Challenge 2020 Division 1
Chefina and Swap, Chef and Trump Cards, Find XOR, Ada Matrix
August Lunchtime 2020 Division 2
Mode of Frequencies, Ratings and Rankings, Alien Invasion , Game on a Strip
October Challenge 2020 Division 1
Inversions, Positive AND, Replace for X, D-Dimensional MST
Russia