回文句或单词

Question

Tom is asked to code the logic to find if a given sentence or a word is a palindrome or not. Help him to code this logic in Python. Remember to do a case insensitive check. Refer the sample input and output statements for more clarifications.

Sample Input 1: Enter the word : Madam

Sample Output 1: Yes, the string is a palindrome !

Sample Input 2: Enter the word : Python

Sample Output 2: No, the string is not a palindrome !

Sample Input 3: Enter the word : Was it a rat I saw

Sample Output 3: Yes, the string is a palindrome !

我编码如下：

t1 = input('Enter the word : ').lower() 
if( t1==t1[::-1])
   print('Yes, the string is a palindrome !')
else:
   print('No, the string is not a palindrome !')

我仍然无法通过所有测试用例。任何人都可以帮我弄清楚吗？

Answer 1

您应该忽略不是字母的字符（如空格），因此您可以filter them out然后进行检查：

t1 = input("Enter the word: ").lower()
# filter out non-letters
t1 = "".join(x for x in t1 if x.isalpha())
if t1 == t1[::-1]:
    print("It is a palindrome")
else:
    print("It is not a palindrome")

Answer 2

第三个测试用例表明检查中不应考虑空格。因此，请通过以下任一方式忽略它们：

t1 = input().lower().replace(' ', '')

或

t1 = ''.join(input().lower().split())

Answer 3

我真的不会使用简单的“翻转”来比较回文，使用循环仍然是理想的，因为它避免了必须操纵整个字符串：

def isPalindrome(word):
    word = word.lower().replace(" ", "")
    start, end = 0, len(word)-1
    while start < end and word[start] == word[end]:
        start += 1
        end -= 1
    return start >= end

回文句或单词

Palindrome Sentence or word

python

palindrome

python-3.x