CompSci 101 Fall 2024 Exam 2 Solutions

Problem 1
	Part A:
		5
		[0, 1, 2, 3, 4]
		['gary', 'pearl', 'sandy', 'spongeBob', 'squidward']
		Error
	Part B:
		3
		"moe's tavern"
		Error
		marge&homer'
	Part C:
		{4,5,6}
		{1,2}
		{4,5,6,9,10}



Problem 2
	Multiple solutions possible for all parts.

	Part A:   [x % 5 for x in values if x % 2 == 0]
	Part B:   [(k, v) for k, v in var.items() if k > 8 or sum(v) < 10]
	Part C:   sorted([x for x in set(nums2) - set(nums1)])
	Part D:   [word for word in words if len(word) > 3 and word.count('a') <= 2]



Problem 3
	Part A:
	  Infinite loop.
	Part B:
		def build_count_dict(lst):   # fixed version
	    count_dict = {}
	    i = 0

	    while i < len(lst):
	        item = lst[i]

	        # Error #1: missing default value
	        if item not in count_dict and str(item).isalpha():
	            count_dict[item] = 0

	        if str(item).isalpha():
	            count_dict[item] += 1

	        # Error #2: missing updated i variable
	        i += 1

	    return count_dict



Problem 4
	Multiple solutions possible.

	def calculate_total(purchases):
	  total_spent = {}

	  for purchase in purchases:
	      item, quantity, price = purchase.split(":")
	      quantity = int(quantity)
	      price = float(price)

	      if item in total_spent:
	          total_spent[item] += quantity * price
	      else:
	          total_spent[item] = quantity * price

	  return total_spent



Problem 5
	Multiple solutions possible.

	def filter_words(sentences):
	  result = set()

	  for sentence in sentences:
	      words = sentence.split()
	      for word in words:
	          if len(word) > 5 and word[0] in 'aeiou':
	                  result.add(word)

	  return sorted(result)



Problem 6
	Multiple solutions possible.

	def most_wins(records):
	  if not records:
	      return []

	  wins_dict = {}

	  for record in records:
	      school, scores = record.split(':')
	      scores = scores.split(',')

	      total_wins = 0
	      for score in scores:
	          total_wins += int(score)

	      if school not in wins_dict:
	          wins_dict[school] = 0
	      wins_dict[school] += total_wins

	  result = list(wins_dict.items())
	  return result