Computer Science II Assignment 7

CSC 242: Introduction to Computer Science II
Assignment 7

Reading
Read Chapter 10 in Introduction to Computing using Python: An Application Development
Focus by Ljubomir Perković.
Logistics
In this class programming assignments may be completed in consultation with up to two other
classmates. You must identify the classmates with whom you collaborate in a comment at the top
of the assignment, and the number of collaborators on any assignment may not exceed two
other people. You must also submit a comment in your submission for each assignment that
describes in detail how each collaborator contributed to the assignment. If you did not
collaborate with anyone on the assignment, you must include a comment that says that. You may
not under any circumstances discuss the assignments with classmates other than your identified
collaborators. Working so closely with anyone other than your identified collaborators, Mr. Zoko
or the teaching assistant, so as to produce identical or near identical code is a violation of the
Academic Integrity policy. This policy will be strictly enforced.
Please include the following with your assignment submission:
1. A comment at the top of your Python file identifying any classmates with whom you
discussed or in any other way collaborated on the assignment. You may work (directly or
indirectly) with no more than two other people.
2. Add a comment at the top of your Python file that describes for each person what they
contributed to the assignment. This must be at least 2-3 sentences and be very specific
and detailed.
A submission that does not include a list of collaborators and a comment indicating how you
collaborated with classmates will earn a 0. If you worked alone you must put a comment at the
top of your file that indicates that or you will also receive a 0. There will be no exceptions to this
rule.
Again, you are subject to all the rules specified in the Academic Integrity policy. Please read it
carefully before beginning this assignment.
Assignment
Please remember that you are not allowed to consult online resources when completing
homework assignments. If you have questions about this assignment, please contact me.
Implement the functions below in a file called csc242hw7.py a template for which has been
provided on the D2L site.
The functions written for this assignment must be recursive (Problems 1-5) and must not use
global variables. Do not modify the function names or parameters in the template file. The
functions may not use loops. In some cases, certain built-in Python functions are disallowed.
Please read the problem description carefully. Function that are described as returning values
should not do any printing. Solutions that do not follow these guidelines will not earn full credit,
even if they produce the correct results in all cases.
Please note, local variables are absolutely fine in any of the functions.
1. Write a recursive function recLessThan() that takes a an integer and prints a
“greater than symbol” pattern using the character ‘*’. The parameter represents the
largest indent of the pattern. If n is 0 or negative the function doesn't print anything.
The following shows several examples of patterns using different values of n.
2. Write a recursive function recHourGlassShape() that takes a character and two
integers n and indent as parameters and prints an hour glass pattern using the
character. The number of characters in the top line of the pattern and in the bottom
line of the pattern (i.e. the biggest lines for each of the characters) is n. The indent
parameter represents the indentation used in the first line of the pattern and in the last
line of the pattern. The indentation increases in the top triangle (using the first
character) and decreases in the bottom triangle (using the second character). If n is 0
or negative or one of the characters is the empty string, the function doesn't print
anything. You should assume that the indent parameter will be non-negative (i.e. >=
0). The following shows several examples of patterns using different characters,
values of n, and amount of indentation.
3. Write a recursive function recListAdder () that takes a list as a parameter and
returns a number with all sum of all the integers and floatsnt found in the list. Recall
that you can determine whether an item is an int or float by writing type(item) == int,
type(item)==float. The following shows several sample runs of the function. You
should test with other inputs as well.:
4. Write a recursive function recEvenNumberCount() that takes a one-dimensional list
of strings as a parameter and returns the count of even numeric types (float or in)
that are found in the list. Recall that you can determine whether an item is an int or
float by writing type(item) == int, type(item)==float. The only list functions you are
allowed to use are len(), indexing (lst[i] for an integer i), or slicing (lst[i:j] for integers
i and j). In particular, the function should not in any way alter the list passed as a
parameter. The following shows several sample runs of the function. You should test
with other inputs as well.:
5. Write a recursive recStringMerge that takes two string and returns a single string
that is a combination of all the strings. The only string functions you are allowed to
use are len(), indexing (lst[i] for an integer i), or slicing (lst[i:j] for integers i and j).
The following shows several sample runs of the function. You should test with other
inputs as well.:
Submitting the assignment
You must submit the assignment using the assignment 7 dropbox on the D2L site. Submit a
Python file (csc242hw7.py) with your implementation in it and comments describing your
collaboration status. Submissions after the deadline listed above will be automatically rejected
by the system. See the syllabus for the grading policy.
Grading
The assignment is worth 100 points. Each recursion question is worth 20 points. Any student
who does not submit comments in the Python file describing the contributions of each team
member or indicating that he/she worked alone will earn a 0 on the assignment.