January Challenge 2015
Sereja and Number Division 2, Chef and Stones
February Challenge 2015
Chef and Chain, Let us play with rank list, Chef and Equality
March Challenge 2015
Chef and Notebooks, Devu and his Class
April Challenge 2015
Chef and Interview, Broken Telephone, Chef and Piano Scales
May Challenge 2015
Set Difference , Chef and new recipe
June Challenge 2015
Steady tables, Chef and Memory Limit, Chef and Polygons
July Challenge 2015
Chef and Cube, Bread, Na2a and lucky stone
August Challenge 2015
Way Out, Gravity Guy, Cooking Machine, Aditi and Magic Trick
September Challenge 2015
Cracking the Code, Lighthouses, Bank robbery, Count Steps in Matrix, Chain of Doughnuts
October Challenge 2015
Time measure, Count Subarrays, Who dares to be a millionaire, Rupsa and Equilateral Triangle
India