README

Project: Binary Tree With Ternary Strings

Author: DrkWithT / thelonecodist

Started: Oct 2021

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Summary:

This small project is a C implementation of a binary tree data structure, but with a twist. The twist is that ternary strings (base 3 digits like 0 to 2) are used to traverse the tree to add/get nodes. However, the implementation lacks node removal. I just made this in one day or so.

This project uses loosely "object-oriented" C. Thus, the typedefs and their functions are called "objects".

Loose Specifications:

Input:
The ternary strings used to add nodes at a location follow these rules:

1. They must not be empty or malformed with non-ternary digits.
2. 0 goes to the root of the tree.
3. 1 goes to the left child of the currently node.
4. 2 goes to the right child of the current node.

Structures:

1. TreeNode: A type defined C struct that holds three data fields: int data, TreeNode* left, and TreeNode* right.
2. BinTree: The main binary tree structure, which encapsulates a root TreeNode that points to its immediate descendants, and so on. It holds TreeNode* root, size_t bt_size, and size_t bt_depth. Size indicates the number of nodes. Depth indicates the number of generations.

Main Functions:

1. TreeNode_Init(TreeNode* self, int _data): Initializes a single TreeNode struct with null pointers for children.
2. TreeNode_addLeft(), TreeNode_addRight(): Both of these add child nodes to the left or right of the parents node, respectively.
3. TreeNode_freeAll(): Does a simple recursive deallocation of all nodes, traversing the pointers. The link to the StackOverflow post I referenced is in the code comments.
4. BinTree_Init(BinTree* self, int root_data): Initializes the BinTree structure with a single root node and both depth and size of 1.
5. BinTree_addNodeAt(BinTree* self, const char* path, int _data): Attempts to add a node to the tree at the ending location of the path string. It fails when the path is inside the tree. Neither will it add a node outside the tree by >= 2 levels. A single level past some edge of the tree is okay for adding.
6. BinTree_setDataAt(BinTree* self, const char* path, int _data): Attempts to set data at the end location of the given path. It fails when the path is empty or out of bounds.
7. BinTree_getDataAt(BinTree* self, const char* path): Attempts to retrieve an integer stored in the path's ending location within the tree. It fails when the path is empty or out of bounds.

Other Notes:
I forgot to put more extensive tests for the node addition and getting functions. I'll do that later. Also, this is meant to compile on Linux-based systems, and I am unsure of how it would work for Windows...