Com Sci 105
Fundamentals of Computer Programming
Autumn 1998

Assignment 5

The purpose of this assignment is to give you more practice with recursion in Scheme. Run all problems MacGambit, and hand them in online as well as in a printout. For each problem, supply about 5 test cases to show that your procedures do work as desired. Turn in the tests (input & output) with the electronic copy, and with the hard copy as well.

• Write the function "repeated" in Scheme using recursion. Remember that "repeated" takes a function and a number as input and returns a function. What is the criterion for a function to be a valid argument to "repeated"?
• Write a predicate "prime" that takes an integer as input and returns true if and only if the integer is prime. (Hint: Use a helper procedure "divides' that takes two integers as input and returns true if there is some integer between 2 and the first integer that divides the second integer)