* fix: initialise properly res, set properly size of ans
* test: add check with empty input
* style: use const reference as input type
* refactor: add ind_type
* style: use reverse interators to b
* style: use auto in definition of idx
* updating DIRECTORY.md
* style: clean-up includes
* style: use std::string::size_type in definition of ind_type
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Co-authored-by: github-actions[bot] <github-actions@users.noreply.github.com>
Co-authored-by: David Leal <halfpacho@gmail.com>