1. [10 points] Write a regular expression that defines an integer constant in C++. The whole numbers may optionally have a leading negative sign. If the number is in hexadecimal, it starts with OX and can contain the digits 0 to 9 and the letters A to F. Octal constants start with zero and can only contain the digits 0 to 7. 2. [10 points] Draw a Finite State Automaton to recognize C++ integer constants. 3. Write a regular expression that defines a string that starts with an "A", ends with a different "A" and has an even number (zero is an even number) of B's in the middle mixed up with any number of additional A's. For example: ABBA or ABABBABA or ABBBBABBA or AA 4. [10 points] Draw a Finite State Automaton to recognize the above strings