replace word with s, comment change to more succinct

Author: miguelHx

Python/chapter01/1.4 - PalinPerm/miguel_1.4_sol.py

@@ -11,20 +11,20 @@
 from typing import Callable
 
 
-def is_permutation_of_palindrome(word: str) -> bool:
+def is_permutation_of_palindrome(s: str) -> bool:
     """
-    Checks if a word is a palindrome by analyzing the frequencies of characters.
+    Checks if a string is a palindrome by analyzing the frequencies of characters.
     A palindrome is a word or phrase that is the same forwards and backwards.
     When determining character frequencies, word will be put to lowercase
     and spaces will not be counted
     A palindrome also has the following property:
-    * all characters have an even count or all except one are even
+    * at most one character appears an odd number of times
     Runtime: O(n)
     Space Complexity: O(n)
-    :param word: the word we check, 'word' is a possible permutation of a palindrome
-    :return: true if word is a permutation of a palindrome, false otherwise
+    :param s: the string we check, 's' is a possible permutation of a palindrome
+    :return: true if s is a permutation of a palindrome, false otherwise
     """
-    char_frequencies = collections.Counter(word.lower().replace(' ', ''))
+    char_frequencies = collections.Counter(s.lower().replace(' ', ''))
     num_odd_freq_chars = 0
 
     for key, val in char_frequencies.items():
@@ -35,21 +35,21 @@ def is_permutation_of_palindrome(word: str) -> bool:
     return True
 
 
-def _is_palindrome(word: str) -> bool:
+def _is_palindrome(s: str) -> bool:
     """
-    Checks if word is a palindrome by checking if the forward version is the same as the backward version.
+    Checks if s is a palindrome by checking if the forward version is the same as the backward version.
     A palindrome is a word or phrase that is the same forwards and backwards.
     Whitespace will not be considered when determining palindrome.
     This function is case insensitive.
-    :param word: the word we check, possible permutation of a palindrome
-    :return: true if word is a palindrome, false otherwise
+    :param s: the string we check, possible permutation of a palindrome
+    :return: true if s is a palindrome, false otherwise
     """
-    word_no_spaces = word.replace(' ', '').lower()
-    reversed_word = word_no_spaces[::-1]
-    return word_no_spaces == reversed_word
+    s_no_spaces = s.replace(' ', '').lower()
+    reversed_s = s_no_spaces[::-1]
+    return s_no_spaces == reversed_s
 
 
-def is_permutation_of_palindrome_brute_force(word: str) -> bool:
+def is_permutation_of_palindrome_brute_force(s: str) -> bool:
     """
     Given a string, this function will return whether the string is a permutation of a palindrome.
     A palindrome is a word or phrase that is the same forwards and backwards.
@@ -62,12 +62,11 @@ def is_permutation_of_palindrome_brute_force(word: str) -> bool:
     Space complexity is O(n!)
     Given:      Expect:
     Tact Coa        True (permutations: "taco cat", "atco cta")
-
-    :param word: the string that we want to check for perm of a palindrome
-    :return: True if word is a palindrome, False otherwise.
+    :param s: the string that we want to check for perm of a palindrome
+    :return: True if s is a palindrome, False otherwise.
     """
-    word_no_spaces = word.replace(' ', '')
-    perms = [''.join(p) for p in it.permutations(word_no_spaces)]
+    s_no_spaces = s.replace(' ', '')
+    perms = [''.join(p) for p in it.permutations(s_no_spaces)]
     for p in perms:
         if _is_palindrome(p):
             return True
@@ -86,8 +85,8 @@ def _run_tests(self, f: Callable[[str], bool]) -> None:
             ("", True),
             ("a", True)
         ]
-        for word, expected in cases:
-            self.assertEqual(f(word), expected, msg=word)
+        for s, expected in cases:
+            self.assertEqual(f(s), expected, msg=s)
 
     def test_is_permutation_of_palindrome(self):
         self._run_tests(is_permutation_of_palindrome_brute_force)
@@ -106,8 +105,8 @@ def test_is_palindrome(self):
             ("Tacoo Cat", True),
             ("Tacooo Cat", True)
         ]
-        for word, expected in cases:
-            self.assertEqual(_is_palindrome(word), expected, msg=word)
+        for s, expected in cases:
+            self.assertEqual(_is_palindrome(s), expected, msg=s)
 
 
 if __name__ == '__main__':