Question 1

Solution:

def count_occur(s, c):
   """
    Input: string s, character c
    Output: integer count of the number of times c occurs in s.
   """
		if len(s) == 0:
		    return 0
    elif s[0] == c:
				return 1 + count_occur(s[1:], c)
    else:
				return count_occur(s[1:], c)

Rubric:

• 0 mark is given if Incorrect/ Not Attempted/ used loop / used build-in function.
• 1 mark is given if the base case is correct.
• 2 marks are given if the correct recursive step is written when the character matches the character at the start/end of the current string.
• 2 marks are given if the correct recursive step is written when the character does not match the character at the start/end of the current string.

Question 2

Solution:

Set 1

Set 2

Rubrics

• 1 point will be provided if A is correct. A bonus of 0.5 points will be provided if A = 2.
• 1 point for correct B.