Информатика 9 класс, задача

42...Чтобы два раза не спрашивала: https://ru.wikipedia.org/wiki/%D0%9E%D1%82%D0%B2%D0%B5%D1%82_%D0%BD%D0%B0_%D0%B3%D0%BB%D0%B0%D0%B2%D0%BD%D1%8B%D0%B9_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_%D0%B6%D0%B8%D0%B7%D0%BD%D0%B8,_%D0%B2%D1%81%D0%B5%D0%BB%D0%B5%D0%BD%D0%BD%D0%BE%D0%B9_%D0%B8_%D0%B2%D1%81%D0%B5%D0%B3%D0%BE_%D1%82%D0%B0%D0%BA%D0%BE%D0%B3%D0%BE