May Challenge 2020 Division 2
Isolation Centers, Coronavirus Spread
June Challenge 2020 Division 2
Even Matrix, The Tom and Jerry Game!, Chef and Icecream, Covid Sampling (Challenge), Chef and String, Chef and Price Control
July Challenge 2020 Division 2
Missing a Point, Doctor Chef, Chef and Strings
July Lunchtime 2020 Division 2
Chef and Steps, Maximum Candies
March Challenge 2021 Division 3
No Time to Wait, Maximum Topological Sort, Wireless Electricity (Challenge), Space Arrays, Consecutive Adding, College Life 4, Chef and Groups, Dense Graph, Interesting XOR!, Paparazzi Gennady
April Challenge 2021 Division 2
Boolean Game, Chef and Dice, Destroy the EMP Chip, Worthy Matrix, Tree Permutations, Binary String MEX
May Challenge 2021 Division 2 (Rated)
Xor Equality, Tic Tac Toe, Modular Equation
June Lunchtime 2021 Division 2
From Rational to Binary, False Number, Unpleasant Ones
India