June Challenge 2017
Chef and the Feast, A Good Set, Pairwise union of sets, Xenny and Coin Rankings, Triplets
July Challenge 2017
Chef and Sign Sequences, Whats in the Name, Calculator
September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Little Chef and Sums
October Challenge 2017
Counter Test For CHEFSUM, A Balanced Contest, Max Mex
November Challenge 2017
Chef and Intersection Line, Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
September Cook-Off 2017
Statistics Construction, Subsequence Equality
June Lunchtime 2017
Maximum Unique Segment, Two Numbers
October Lunchtime 2017
Buggy Calculator, Maximum Number
December Lunchtime 2017
Days in Month, Strange Function
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle, String Merging, Partition the numbers
March Challenge 2018 DIV 2
Pishty and Triangles, Minion Chef and Bananas, Minions and Voting, Chef and Glove, Mix the Colors, A Big Sale, Chef and Easy Problem
April Challenge 2018 Division 1
Chef and Array (Challenge), Highway Crossing, Count Good Prefixes
August Challenge 2018 Division 1
Modular GCD, Interactive Matrix
India