* Update avl_tree.md
* Remove the empty space
* Simplify the heading of the paperbook chapter
* Update hash_map_open_addressing.go to the latest version
* Improvements
* Sync recent changes to the revised Word.
* Revised the preface chapter
* Revised the introduction chapter
* Revised the computation complexity chapter
* Revised the chapter data structure
* Revised the chapter array and linked list
* Revised the chapter stack and queue
* Revised the chapter hashing
* Revised the chapter tree
* Revised the chapter heap
* Revised the chapter graph
* Revised the chapter searching
* Reivised the sorting chapter
* Revised the divide and conquer chapter
* Revised the chapter backtacking
* Revised the DP chapter
* Revised the greedy chapter
* Revised the appendix chapter
* Revised the preface chapter doubly
* Revised the figures
* feat(go): support hash map chaining
* feat(go): support hash map open address
* feat(go): support simple hash
* feat(go): support top k heap
* feat(go): support subset sum I
* feat(go): support subset sum native
* feat(go): support subset sum II
* fix(go): fix some problem