Questions

This practice is intended to help you become more comfortable with code writing style questions, though the final will have other types of questions as well.

Solutions for each problem can be found at the bottom of this page. Keep in mind that there may be multiple solutions to each problem.

Function Writing

1. Write a function called reverse_multiply. Given a list[int], reverse_multiply should return a list[int] with the values from the original list doubled and in reverse order.
   Example: reverse_multiply([1, 2, 3]) should return [6, 4, 2].

2. Write a function called free_biscuits. Given a dictionary with str keys (representing basketball games) and list[int] values (representing points scored by players), free_biscuits should return a new dictionary of type dict[str, bool] that maps each game to a boolean value for free biscuits. (True if the points add up to 100+, False if otherwise)
   Example: free_biscuits({ “UNCvsDuke”: [38, 20, 42] , “UNCvsState”: [9, 51, 16, 23] }) should return { “UNCvsDuke”: True, “UNCvsState”: False }.

3. Write a function called multiples. Given a list[int], multiples should return a list[bool] that tells whether each int value is a multiple of the previous value. For the first number in the list, you should wrap around the list and compare this int to the last number in the list.
   Example: multiples([2, 3, 4, 8, 16, 2, 4, 2]) should return [True, False, False, True, True, False, True, False].

4. Write a function called merge_lists. Given a list[str] and a list[int], merge_lists should return a dict[str, int] that maps each item in the first list to its corresponding item in the second (based on index). If the lists are not the same size, the function should return an empty dictionary.
   Example: merge_lists([“blue”, “yellow”, “red”], [5, 2, 4]) should return {"blue": 5, "yellow": 2, "red": 4}.

Class Writing

5. Create a class called HotCocoa with the following specifications:
   1. Each HotCocoa object has a bool attribute called has_whip, a str attribute called flavor, and two int attributes called marshmallow_count and sweetness.
   2. The class should have a constructor that takes in and sets up each of its attribute’s values.
   3. Write a method called mallow_adder that takes in an int called mallows, increases the marshmallow_count by that amount, and increases the sweetness by that amount times 2.
   4. Write a method called calorie_count that returns a float. If the flavor of the HotCocoa is “vanilla” or “peppermint”, increase the calorie count by 30, otherwise increase it by 20. If the HotCocoa has whipped cream (has_whip is True), increase the calorie count by 100. Finally, increase the calorie count by half the number of marshmallows. The calorie count should be calculated and returned when this method is called.
6. Create a class called TimeSpent with the following specifications:
   1. Each TimeSpent object has a str attribute called name, a str attribute called purpose, and an int attribute called minutes.
   2. The class should have a constructor that takes in and sets up each of its attribute’s values.
   3. Write a method called add_time that takes in an int and increases the minutes attribute by this amount. The method should return None.
   4. Write a method called reset that resets the amount of time that is stored in the minutes attribute. The method should return the amount that was stored in minutes.
   5. Write a method called report that prints a line reporting information about the current TimeSpent object. Suppose a TimeSpent object has name = “Ariana”, purpose = “screen time”, and minutes = 130. The report method should print: “Ariana has spent 2 hours and 10 minutes on screen time.”

Solutions

Function Writing

Class Writing