Consider the circuit below $4-$bits Adder$-$subtractor, suppose we want to implement subtraction using $2\text{'}$s complement only. The inputs are A and B four bits, and CTRL bit. The outputs are the four$-$bits difference and the sign bit. Implement it using hierarchal design. Provide the code, and screenshot of the wave diagrams for inputs and outputs. $($Hint: you have to use modules of Adder$\_4$bits, Full$\_$Adder, and Half$\_$Adder modules$).$

Full code including Adder$\_4$bits, Full adder and half adder modules