Update infix to postfix (#3817)
* add test to infix_to_postfix_conversion
* fixed pre-commit error
* fixed build error
* updating DIRECTORY.md
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com> D
Du Yuanchao committed
786b32431cd1d0f57ec4b79a009959da8a2fe06c
Parent: d8f573c
Committed by GitHub <noreply@github.com>
on 11/1/2020, 4:35:31 PM