SAT Solver Project

create some test cases for DPLLGui to check if the problems are in the implementation or some parts of the code are not running correctly in the interface implementation. The representation of formulas as input from user should be with digits. The following validations should be implemented:
1- If the user types anything but digits it should display a message to represent their formula in terms of numbers.
2- If the user types nothing then a message should appear to ask the user for input again.
3- Otherwise perform DPLL (check where it fails that I always get unsat formula)