Sherlock and Coprime Subset
Largest Lexicographical Rotation II
Shil and Greedy approach
Roy and Coin Boxes
We Are On Fire
Beautiful primes
Codeforces Round 515 (Div. 3) F. Yet another 2D Walking
2018-2019 ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) E. Getting Deals Done
Codeforces Round 521 (Div. 3) F2. Pictures with Kittens (hard version)
Codeforces Round 530 (Div. 1) B. Nice table