Challenge 08: Palindrome Permutation

Problem

Given a phrase, you are to determine if any permutation of the phrase (ignoring whitespace and punctuation) is a palindrome, which is a phrase that reads the same forwards and backwards. For instance, "taco cat" is an example of a palindrome.

Input

You will be given a series of phrases from standard input in the following format:

phrase1
phrase2
...

Each line is considered a separate phrase, which can consist of letters, numbers, spaces, and punctuation.

Output

For each input phrase, output a statement saying:

"phrase" is a palindrome permutation

if the input phrase is a palindrome permutation. Otherwise, output:

"phrase" is a not palindrome permutation

Note: You should ignore numbers, spaces, and punctuation in determining if a phrase is a palindrome permutation.

Example

Given the following input:

civic
ivicc
civil
livci

Your program should output the following:

"civic" is a palindrome permutation
"ivicc" is a palindrome permutation
"civil" is not a palindrome permutation
"livci" is not a palindrome permutation

Requirements

Your solution must meet the following requirements:

1. You must implement and utilize an is_palindrome(s) function that determines if a string s is a palindrome permutation in O(n) time using a std::unordered_set or std::unordered_map.

Submission

To submit your solution, you must initiate a Merge Request in your private assignments repository and assign it to the appropriate TA from the Challenge 08 - TA assignment list.

$ cd path/to/repo                   # Go to your repository
$ git checkout master               # Make sure we are on master branch
$ git pull                          # Make sure we have changes for GitLab
$ git pull upstream master          # Fetch and merge upstream changes
$ git checkout -b challenge08       # Create challenge08 branch
...                                 # Do your work
$ git commit                        # Commit your work (can do this multiple times)
$ git push -u origin challenge08    # Push branch to GitLab