LeetCode/NeetCodeRoadmap/Arrays_and_Hashing/125_Valid_Palindrome.py
2023-08-30 09:13:13 -07:00

59 lines
1.7 KiB
Python

import string
import math
def isPalindrome(s):
"""
:type s: str
:rtype: bool
"""
# Create a translation table to remove uppercase letters and special characters
# translation_table = str.maketrans("","", string.punctuation + string.whitespace)
translation_table = ''.join(c.lower() if c.isupper() or c.isalnum() else '' for c in s if c.isalnum() or c in string.whitespace)
# print(translation_table)
if len(translation_table) == 2:
if translation_table[0] == translation_table[1]:
return True
else:
return False
# Use the translation table to remove uppercase letters and special characters
# upper_string = s.translate(translation_table)
# lower_string = upper_string.lower()
lower_string = translation_table
half = len(lower_string)/2
# Round the value down since middle value doesn't matter
if len(lower_string)%2 != 0:
halfdown = int(math.floor(half))
else:
halfdown = int(half)
# print(halfup)
# print(halfdown)
first = []
second = []
print(lower_string)
for i in range(halfdown):
# print(i)
# print(lower_string[i])
first.append(lower_string[i])
if len(lower_string)%2 != 0:
for j in range(halfdown+1, len(lower_string)):
second.insert(0, lower_string[j])
else:
for j in range(halfdown, len(lower_string)):
second.insert(0, lower_string[j])
print(first)
print(second)
if first == second:
return True
else:
return False
print(isPalindrome("A man, a plan, a canal: Panama"))
print(isPalindrome("aa"))
print(isPalindrome("0P"))
print(isPalindrome("abba"))