May Challenge 2015
Devu and binary String, Chef and Prime Divisors, Set Difference , Chef and new recipe, Chef and Cake, Devu and his three Hands
June Challenge 2015
Anticommutative implication, Chef and String, Chef and Polygons, Chef and Memory Limit, Chef and His Friend, Steady tables
September Challenge 2015
Chain of Doughnuts, Count Steps in Matrix, Lighthouses
November Challenge 2015
Chef and collection of stamps, Eugene and function, Simple Sum, Chef and cakes
Vietnam