September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Fill The Matrix, Little Chef and Sums, Sereja and Commands
October Challenge 2017
A Balanced Contest, Counter Test For CHEFSUM, Max Mex, Chef and a great voluntary Program
December Challenge 2017
Total Diamonds, Chef And his Cake, Chef And Easy Xor Queries, Penalty Shoot-out, Chef and Hamming Distance of arrays
October Cook-Off 2017
Chef and Counting Test, Chef and Weird Queries, Chef and Employment Test
December Cook-Off 2017
Beautiful Array, Football Match
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging, Partition the numbers
March Challenge 2018 DIV 1
Pishty and Triangles, Chef and Easy Problem, Chef and Gcd Queries, Mix the Colors, Minions and Voting
India