September Challenge 2014
Chef and Left-Right, Fun with Rotation
November Challenge 2014
Chef and Segment Game, Distinct Characters Subsequence, Let us construct palindrome
January Challenge 2015
Chef and Stones, Sereja and Votes, Gcd Queries
January Cook-Off 2015
Suraj goes shopping, Tojo hates probabilities
February Challenge 2015
Chef and Chain, Chef and Strange Formula, Chef and Strings, Let us play with rank list, Chef and Equality
March Challenge 2015
Chef and Notebooks, Devu and his Class, Sign Wave
April Challenge 2015
Chef and Piano Scales, Chef and Array, Division of Lands, Chef and Interview, Count Sequences, Broken Telephone
June Challenge 2015
Chef and Memory Limit, Chef and Polygons
July Challenge 2015
Bread, Na2a and lucky stone, Chef and Cube
August Cook-Off 2015
Chef and the XORed Number , Chef and the Wildcard Matching
June Lunchtime 2015
Chef and Submatrix, Chef and Two Strings
September Lunchtime 2015
Sum of palindromic numbers
India