February Challenge 2015
Time to Study Graphs with Chef, Chef and Strange Formula, Chef and Strings, Let us play with rank list, Chef and Equality, Chef and Chain
March Challenge 2015
Sign Wave, Matrix, Devu and his Class, Sereja and Random Array, Chef and Problems, Chef and Notebooks, Count Substrings
April Challenge 2015
Count Sequences, Chef and Array, Chef and Interview, Broken Telephone, Inversion sorting, Chef and Piano Scales
August Challenge 2015
Way Out, Chef and insomnia, Aditi and Magic Trick, Devu And Churu , Gravity Guy, Cooking Machine
April Challenge 2018 Division 2
Weight of Numbers, Count Good Prefixes, Average of Pairs, Workers
April Challenge 2019 Division 2
Mininum XOR over Tree, Fencing, Subtree Removal, Maximum Remaining, Friend or Girlfriend, Playing with Numbers
August Challenge 2019 Division 1
Guddu and his Mother, Dilemma
Ukraine