October Challenge 2017
Max Mex, Counter Test For CHEFSUM, A Balanced Contest, Chef and a great voluntary Program
November Challenge 2017
Chef Hates Palindromes, Chef goes Left Right Left, Periodic Palindrome Construction, Villages and Tribes
December Challenge 2017
Total Diamonds, Chef And his Cake, Penalty Shoot-out, Chef and Hamming Distance of arrays
January Challenge 2018
Rectangle, Partition the numbers, String Merging, Maximum Score, K-Concatenation
February Challenge 2018
Chef And His Characters, Chef And The Patents, Points Inside A Polygon, Car-pal Tunnel, Permutation and Palindrome
August Challenge 2018 Division 2
Modular GCD, Spell Bob, Problem Sort, Sheokand and Number
November Challenge 2018 Division 2
Chef and Ridges, Appy Loves One, Magician versus Chef 2, Chef and Difficult Contests, Chef and Happiness
October Challenge 2018 Division 2
Chef and Circles, Byte to Bit, Chef and Serves, Chef and Surprise Chessboard, Minimize Digitsum, Beautiful Bricks, Appy and Balloons
October Lunchtime 2018 Division 2
Three Friends, Coloring the Grid, Weird Question
January Challenge 2019 Division 1
Yet Another Problem About Sequences, Different Neighbours, Lucky Number Game, Distinct Pairs, A Pizza Slice
February Challenge 2019 Division 1
Manhattan Rectangle, Guess It Right, Chef and Secret Ingredients, Art of Balance
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