##Topics completed:

• Unit tests (Google test framework used).
  ./tests/

• Overload operator[][]

• Write simple iterator

• Multithreading (std::async and std::thread)

• Metaprogramming

• Compete README (add completed topics, search for other mistakes, add compile and launch instructions for console).

• Did not create separate git branch for each topic.
  There were problems when committing completed tasks if another task was already started, on which the difficulty arose.
• All test data is hardcoded.
  If want to change or add some test data recompile of whole project is needed.
• Test logging occurs to stdout.
  Better to write logs to some file.
• Executable for tests. Tests should be executed once after compilation, not at every launch.