Shortest Path Revisited
Number of divisors
Maximum size of a set
Remove Interval
Codeforces Round 720 (Div. 2) C. Nastia and a Hidden Permutation
Divide by Zero 2021 and Codeforces Round 714 (Div. 2) D. GCD and MST
Codeforces Round 716 (Div. 2) D. Cut and Stick
Educational Codeforces Round 109 (Rated for Div. 2) C. Robot Collisions
Codeforces Round 724 (Div. 2) D. Omkar and Medians
Problem C2: Back in Black (Chapter 2)