February Challenge 2017
Chef and His Apartment Dues
March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Greedy Candidates
September Challenge 2017
Chef and Pick Digit, Minimum Good Permutation, Little Chef and Sums
November Challenge 2017
Villages and Tribes, Periodic Palindrome Construction, Chef goes Left Right Left
September Lunchtime 2017
Chef and Cook-Off Contests
January Challenge 2018
K-Concatenation, Maximum Score, Rectangle
January Lunchtime 2018
Chef and Game with Sequence
February Challenge 2018
Permutation and Palindrome, Chef And His Characters, Chef And The Patents
March Challenge 2018 DIV 2
Chef and Easy Problem, A Big Sale, Mix the Colors, Chef and Glove, Minions and Voting, Minion Chef and Bananas
March Cook-off 2018 Division 2
Chef Restores a Matrix, Chef Judges a Competition
April Challenge 2018 Division 2
Workers, Average of Pairs, Weight of Numbers, Chef and Array (Challenge), Count Good Prefixes
September Challenge 2018 Division 2
Magician versus Chef, War of XORs, Chef and Adventures
November Challenge 2018 Division 2
Chef and Difficult Contests
October Challenge 2018 Division 2
Appy and Balloons , Byte to Bit, Chef and Serves, Minimize Digitsum
June Lunchtime 2019 Division 2
Ping Paja Pong, Magda and Silly Pairs
November Lunchtime 2019 Division 2
Planting Trees, Compress the List
India