* Add "reference" for EN version. Bug fixes.
* Unify the figure reference as "the figure below" and "the figure above".
Bug fixes.
* Format the EN markdown files.
* Replace "" with <u></u> for EN version and bug fixes
* Fix biary_tree_dfs.png
* Fix biary_tree_dfs.png
* Fix zh-hant/biary_tree_dfs.png
* Fix heap_sort_step1.png
* Sync zh and zh-hant versions.
* Bug fixes
* Fix EN figures
* Bug fixes
* Fix the figure labels for EN version
* Translation: Update binary_tree.md
simplified some parts while others added a few words to make it clearer
* translation: Update binary_tree.md
edited most of the stuff that QiLOL has suggestion, again thanks QiLOL for the review
* translation: Update binary_tree.md
changed to simpler words instead.
Did not update the 2nd part, as I'm waiting for Khrahets to make the final decision
* Translation: Update index.md
simplified the words using "vibrant" instead. used illustrate instead of demonstrate because I'm thinking the image "illustrates" the concept.
* Translation: Update index.md
Changed to what yuelinxin has suggested. thanks for the suggestion.
Estevão Goerll
Flamingo
Yudong Jin
K3v123