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Exercise 1: Summing numbers, recursively

Consider the following function, which returns the sum of the numbers from 1 to n.

def recursiveSum(n):
    # Base case
    if n == 1:
        return 1

    # Recursive case
    return n + recursiveSum(n-1)

What is the output for recursiveSum(6)? It may help to a call tree showing the recursive function calls.

Exercise 2: Reversing a string, recursively

Write a function that returns the reverse of a string. It should use a recursive approach.

def recursiveReverse(s):
    return "" # TODO

For example, if we have mystr = "cheddar", then recursiveReverse(mystr) should return "raddehc".

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Exercise 3: Finding vowels in a string, recursively

Write a function that returns a list containing only the vowels in a given string (assumed to be all lowercase). It should use a recursive approach.

def recursiveVowels(s):
    return [] # TODO

For example, if we have mystr = "elephant", then recursiveVowels(mystr) should return ['e', 'e', 'a'].

Exercise 4: Finding anagrams of a string, recursively

Write a function that returns a list of all of the anagrams of a given string. It should use a recursive approach.

def recursiveAnagram(s):
    return [] # TODO

For example, if we have mystr = "cat", then recursiveAnagrams(mystr) should return ["cat", "cta", "act", "atc", "tca", "tac"].

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