February Challenge 2020 Division 2
The Theatre Problem, School of Geometry, Hard Cash, Expected Change
July Challenge 2020 Division 2
Chef and Card Game, Chef and Strings, (Challenge) Dynamic Hull, Expected Repetitions, Doctor Chef, Missing a Point, Chef and Dragon Dens, Chefina and Swaps, LCM Constraints, Ada King
June Lunchtime 2020 Division 2
Maximum AND, Chef and Demonetisation, Increasing Decreasing, Gold Mining, Square Submatrices
Coders' Legacy (Rated for all)
Chef vs Doof, Doof on Cartesian, Doof fires Brackets, Jeremy gets a gift, Unique Substring
Russia