Ikshu and his new year matrix
Chemical Reaction
AltF4 and the beetles
Help the Avengers
Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) D. Full Binary Tree Queries
Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) F. Pathwalks
Educational Codeforces Round 43 (Rated for Div. 2) E. Well played!
Codeforces Round 480 (Div. 2) D. Perfect Groups
Educational Codeforces Round 44 (Rated for Div. 2) D. Sand Fortress
Help Raj play Table Tennis