CMPSC-132: Programming and Computation II Homework 1 (100 points) Due date: May 30th, 2021, 11:59 PM EST Goal: Revise your Python concepts and using them to solve problems using Python’s built-in data types General instructions: • The work in this assignment must be your own original work and be completed alone. • The instructor and course assistants are available on Teams and with office hours to answer any questions you may have. You may also share testing code on Teams. • A doctest is provided to ensure basic functionality and may not be representative of the full range of test cases we will be checking. Further testing is your responsibility. • Debugging code is also your responsibility. • You may submit more than once before the deadline; only the latest submission will be graded. Assignment-specific instructions: • Download the starter code file from Canvas. Do not change the function names or given starter code in your script. • Each question has different requirements, read them carefully and ask questions if you need clarification. No credit is given for code that does not follow directions. • If you are unable to complete a function, use the pass statement to avoid syntax errors Submission format: • Submit your HW1.py file to the Homework 1 Gradescope assignment before the due date. • As a reminder, code submitted with syntax errors does not receive credit, please run your file before submitting. Section 1: Overview of functions Points Name Input type Output type 15 rectangle(perimeter, area) int, int int/bool 20 frequency(numList) list many, dict 20 successors(file) str dict 15 isSorted(num) int bool 15 hailstone(num) list list 15 largeFactor(num) int int Section 2: Function details rectangle(perimeter, area) Returns the longest side of the rectangle with given perimeter and area if and only if both sides are integer lengths. In a rectangle = 2+ 2ℎ = ∗ ℎ Hints: • The built-in round(number) function rounds a number to the nearest integer. • To do integer division (also known as floor division), use the // operator. Floor division, as opposed to true division, discards any fractional result from the output. • the built-in float.is_integer() method returns True if the float instance is finite with integral value, and False otherwise Preconditions: Inputs int perimeter The perimeter of the rectangle expressed as an integer. int area The area of the rectangle expressed as an integer. Outputs int The longest side length for the rectangle that meets the given requirements. False False is returned if no rectangle exists that meets the requirements. Examples: >>> rectangle(14, 10) # Represents a 2x5 rectangle 5 # 5 is the larger of the two sides >>> rectangle(25, 25) # Represents a 2.5x10 rectangle False # 2.5 is not an int Section 2: Function details frequency(numList) Returns the most frequent item in numList and a dictionary with the frequency count of each item in the list. When more than one item has the same frequency, it returns the first item with that frequency in numList as the most frequent item. You may assume numList is a non-empty Python list, but you cannot make assumptions about the contents in the list. You might use the count method, but you are not allowed to use any other Python libraries such as Counter, mode, etc., use str() to convert data to string, or to use the min()/max() methods. Preconditions: Inputs list numList Non-empty list of elements Output many, dict First value is the most frequent item in numList and preserves its data type. Second value is a dictionary with the frequency count of each item in numList Example: >>> frequency([3, 7, 5, 5, 7, 7, 5]) (7, {3: 1, 7: 3, 5: 3}) >>> frequency([3, '7', 5, 5.5, '7', 7, 5.5, 'a', 3, 'a', 'a', 'A']) ('a', {3: 2, '7': 2, 5: 1, 5.5: 2, 7: 1, 'a': 3, 'A': 1}) >>> answer=frequency([6, 5, 7, 7, 7, 5, 5, 5]) >>> answer[0] 5 >>> answer[1] {6: 1, 5: 4, 7: 3} # Don’t forget dictionaries are unsorted collections Section 2: Function details successors(file) Returns a dictionary whose keys are included words (as is), and values are lists of unique successors to those words. The first word of the txt file is always a successor to ".". Be careful with punctuation. You can assume the text in the txt file does not contain any contraction words (isn’t, don’t, I’m, etc) but you cannot make assumptions about the spacing or the presence of non- alphanumerical characters. The starter code already contains the code to read the txt file, just make sure the file is in the same directory as your .py file. You must write your code after the file has been read to process the contents. # Open the file and read the contents, the with statement ensures the file properly closed after the file operation finishes with open(file) as f: contents = f.read() # reads the entire file, saving data in contents as string Example Contents of items.txt: We came to learn,eat some pizza and to have fun. Maybe to learn how to make pizza too! >>> print(contents) 'We came to learn,eat some pizza and to have fun.\nMaybe to learn how to make pizza too!' Hints: • The str.isalnum() method returns True if all characters in a string are alphanumeric. • When x = 'We', doing list(x) produces the list ['W', 'e'] Preconditions: Inputs str file A string that contains the name of a txt file that contains multiple strings. Output dict Keys are all included words and punctuation marks, values all successors of that key Example: Contents of items.txt: We came to learn,eat some pizza and to have fun. Maybe to learn how to make pizza too! >>> out=successors('items.txt') >>> out.keys() dict_keys(['.', 'We', 'came', 'to', 'learn', ',', 'eat', 'some', 'pizza', 'and', 'have', 'fun', 'Maybe', 'how', 'make', 'too']) >>> out['.'] ['We', 'Maybe'] >>> out['to'] ['learn', 'have', 'make'] >>> out['fun'] ['.'] >>> out[','] ['eat'] >>> out # Don’t forget dictionaries are unsorted collections {'.': ['We', 'Maybe'], 'We': ['came'], 'came': ['to'], 'to': ['learn', 'have', 'make'], 'learn': [',', 'how'], ',': ['eat'], 'eat': ['some'], 'some': ['pizza'], 'pizza': ['and', 'too'], 'and': ['to'], 'have': ['fun'], 'fun': ['.'], 'Maybe': ['to'], 'how': ['to'], 'make': ['pizza'], 'too': ['!']} Section 2: Function details isSorted(num) Returns a boolean value that determines whether or not all the digits in num appear in ascending order. You can assume num is a positive integer. You are not allowed to cast num to a string, str(num) or to add the digits into a list to traverse or process the number. Hint: • Using floor division (//) and modulo (%) could be helpful here. Floor division by 10 removes the rightmost digit (456//10 = 45), while modulo 10 returns the rightmost digit (456%10 = 6) Preconditions: Inputs int num A positive integer Output bool True if all the digits in num appear in ascending order, False otherwise Example: >>> isSorted(13579) True >>> isSorted(7264578364) False >>> isSorted(2) True >>> isSorted(444444) True >>> isSorted(3759) False Section 2: Function details hailstone(num) Returns the hailstone sequence starting at the given number until termination when num is 1. The hailstone sequence is generated as follows: • If is even, then the next number in the sequence is /2. • If is odd, then the next number in the sequence is 3 ∗ + 1. • Continue this process until = 1 Preconditions: Inputs int num A positive integer used to start the hailstone sequence. Output list Hailstone sequence starting at num and ending at 1. Examples: >>> hailstone(5) [5, 16, 8, 4, 2, 1] >>> hailstone(6) [6, 3, 10, 5, 16, 8, 4, 2, 1] Section 2: Function details largeFactor(num) Returns the largest positive integer that is smaller than num and evenly divides num. Preconditions: Inputs int num A positive integer greater than 1 Output int Largest factor of num that is less than num Examples: >>> largeFactor(15) # factors are 1, 3, 5 5 >>> largeFactor(80) # factors are 1, 2, 4, 5, 8, 10, 16, 20, 40 40 >>> largeFactor(13) # factor is 1 since 13 is prime 1























































































































































































































































































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