* 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
* Modify method name to PascalCase(array and linked list)
* Modify method name to PascalCase(backtracking)
* Modify method name to PascalCase(computational complexity)
* Modify method name to PascalCase(divide and conquer)
* Modify method name to PascalCase(dynamic programming)
* Modify method name to PascalCase(graph)
* Modify method name to PascalCase(greedy)
* Modify method name to PascalCase(hashing)
* Modify method name to PascalCase(heap)
* Modify method name to PascalCase(searching)
* Modify method name to PascalCase(sorting)
* Modify method name to PascalCase(stack and queue)
* Modify method name to PascalCase(tree)
* local check