June Challenge 2017
Chef and the Feast, Xenny and Coin Rankings, Triplets, Pairwise union of sets, A Good Set
July Challenge 2017
Chef and Sign Sequences, Pishty and tree, Whats in the Name, Calculator , IPC Trainers
August Long Challenge 2017
Palindromic Game, Greedy Candidates, Chef and Mover, Chef And Fibonacci Array, Chef and Rainbow Array
September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Little Chef and Sums
April Challenge 2018 Division 2
Weight of Numbers, Count Good Prefixes, Average of Pairs, Workers
January Challenge 2019 Division 2
Yet Another Problem About Sequences, Fancy Quotes, Chef and Modulo Game, Lucky Number Game, Different Neighbours, Distinct Pairs
August Challenge 2019 Division 2
Football, Distribute Apples
February Challenge 2020 Division 2
Long Contest and Cook Off Overlaps, Hard Cash, School of Geometry, The Theatre Problem, No Change Required, Expected Change, Chef and Railway Stations
May Challenge 2020 Division 2
Triple Sort, Sorting Vases, Coronavirus Spread, Chef and Bitwise Product, Isolation Centers
July Challenge 2020 Division 1
LCM Constraints, Chefina and Swaps, Chef and Dragon Dens, Missing a Point, Doctor Chef
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