printPreorder and printPostorder are called from main to print the binary tree argument in a file in preorder and postorder respectively.

Header/source of buildTree contains buildTree function that stores string data from input file in a binary tree. The insert function handles sorting new nodes. New nodes are created with the allocateNode function. The printInOrder function recursively traverse inorder a binary tree and calls writeNodeData in order to write the structure and data of the tree into a file. Before buildTree and printInorder are called in main, the deleteExistingTraversalFile function removes any traversal files created before the currently executing process.

isValidInput function tests if the input strings only contain alphanumeric characters; otherwise, error is thrown

handleKeyboardInput function new accepts user input and writes each entry in temp file called "out.dat"

Created source and header file for handleInput. This file currently has handleKeyboardInput function that creates a temp file called out.dat and returns an error if file is not created. If out.dat already exists then the file is truncated.

main has switch nested in try-catch to detect number of args. 0 and 1 args are valid. +2 args leads to error.