Contribution #426

Problem: ru/11.1.12

Added 11.1.12 11.1.4

Editor: Aliaksandr Melnichenka ( @astrosander )

Time: November 4, 2023 at 02:11 PM

GitHub commit: 8712b8a6772b05c5cb89c44f85006d08044c4aed

+248 -50 lines changed