Cloudy Day
Rust & Murderer
Primes in numbers
Integers: Recreation One
Sum by Factors
Snail
Magnet particules in boxes
Codeforces Round 569 (Div. 1) B. Tolik and His Uncle
Codeforces Round 571 (Div. 2) C. Vus the Cossack and Strings
Educational Codeforces Round 67 (Rated for Div. 2) C. Vasya And Array