https://arena.petlja.org/sr-Latn-RS/competition/20212022egoitst-vezba - racunar
https://arena.petlja.org/sr-Latn-RS/competition/20212022ejoitst-vezba#tab_134775 - poslovan covek
https://codeforces.com/group/Uo1lq8ZyWf/contest/311359/problem/A
https://codeforces.com/gym/105706/problem/A