June Challenge 2017
A Good Set, Chef and the Feast, Xenny and Coin Rankings, Triplets, Pairwise union of sets, Chef and Prime Queries
July Challenge 2017
Two Coins, IPC Trainers, Calculator , Servers (Challenge), Whats in the Name, Tree Expectancy, Pishty and tree, Chef and Sign Sequences
August Long Challenge 2017
Chef and Rainbow Array, Chef And Fibonacci Array, Chef and Mover, Hill Jumping, Palindromic Game, Mathison and the Data Warehouse (Challenge), Greedy Candidates, Strings and Graphs
September Challenge 2017
Chef and Pick Digit, Little Chef and Sums, Fill The Matrix, Weasel does Xor on Tree, Sereja and Functions (Challenge), Sereja and Commands, Minimum Good Permutation
October Challenge 2017
Chef and Magic Arrays, Chef and a great voluntary Program, Chef and Cycled Cycles, Shooting on the array, Max Mex, Counter Test For CHEFSUM, A Balanced Contest, (Challenge) Connecting computers
December Challenge 2017
Total Diamonds, Chef and Hamming Distance of arrays, Red and blue points, Penalty Shoot-out, Chef And Easy Xor Queries, Chef And his Cake
July Challenge 2020 Division 1
LCM Constraints, Chefina and Swaps, Chef and Dragon Dens, Missing a Point, Doctor Chef
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