The code covers following parts :
1.) Converting infix propositional logic expression into a prefix propositional logic expression.
2.) Converting prefix expression into a rooted binary parse tree.
3.) Traverse the parse tree in inorder fashion to output the infix expression.
4.) Computing the height of the parse tree.
5.) Evaluating the truth value to the propositional logic formula, given the truth values of each propositional logic atom.
6.) Converting the given logic formula to Conjunctive Normal Form (CNF).
7.) Checking the validity of the formula.
NOTE: Check headers.c for functions and their definitions used.