September Lunchtime 2015
Sum of palindromic numbers
March Challenge 2016
maximize the sum, Chef And Special Dishes, Palindromic substrings
April Challenge 2016
Help Watson Escape, Chef and Ballons, Chef And Coloring
September Challenge 2016
Chef and digits of a number, Faded Palindromes
October Challenge 2016
Chef and Three Dogs, Chef and Keyboard
November Challenge 2016
Count Permutations, Chef and squares, Task for Alexey
March Cook-Off 2016
Digital clock, Alternating subarray prefix
February Lunchtime 2016
Chef and Socks, Chef and Tic-Tac-Toe
March Challenge 2017
Xenny and Alternating Tasks
June Challenge 2017
A Good Set, Xenny and Coin Rankings, Pairwise union of sets
July Challenge 2017
Chef and Sign Sequences, Whats in the Name
August Challenge 2018 Division 2
Modular GCD, Spell Bob, Sheokand and Number, Problem Sort
April Challenge 2019 Division 2
Friend or Girlfriend, Maximum Remaining
India