1. Write four scheme functions to simulate these four gates. You will then use those functions below.

2.

3.

4.

What to Turn in:

Turn in a single Scheme file (logic.ss file) with the following functions defined (these names start with little L's, not I's or 1's):

• l-and: Takes two 1-bit integers and returns a 1-bit integer
• l-or: Takes two 1-bit integers and returns a 1-bit integer
• l-not: Takes one 1-bit integer and returns a 1-bit integer
• l-xor: Takes two 1-bit integers and returns a 1-bit integer
• fulladdr: Takes three 1-bit integers and returns a pair of two,1-bit integers
  • Note: Result should be a pair: (sum . carry)
  • Note: It must use the functions l-and, l-or, and l-xor.
• n-bit-addr: Takes two lists of 1-bit integers and a 1-bit integer for carry-in. It returns a pair of a list of 1-bit integers, and a 1-bit integer for carry-out
  • Note: You can assume the lists are the same size
  • Note: Result should be a pair: (list-sum . carry-out)
  • Note: It must use the function fulladdr.

Testing:

Make sure you test your functions as you develop them.

fulladdr should behave like this:

Here are some test cases for your n-bit-addr. Of course, you can create more: