How to determine whether a palindrome number is in python

What is a palindrome number:

There is a type of number that is the same number when viewed backwards and forwards, for example : 12321, 1221, 2332, etc. Such numbers are called: palindrome numbers.

Example: Enter a 5-digit number and determine whether it is a palindrome number. That is, 12321 is a palindrome number, the ones digit is the same as the thousands digit, and the tens digit is the same as the thousands digit. Find all the palindromes in the 5-digit number:

Method 1. Use for loop

# 找出5位数中所有的回文数：
for i in range(10000,100000):   # 遍历所有的5位数
    s = str(i)    # 将数字转换成字符串类型，即可以用索引取出每一位上的数字
    if s[0] == s[-1] and s[1] == s[-2]:   # 字符串的索引
        print(i)

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Method 2. Define the function

def is_huiwen(n):
    reversed_str= str(n)
    return reversed_str == reversed_str[-1::-1]   # 
output = filter(is_huiwen,range(10000,100000))
print(list(output))

·The user inputs a 5-digit number to determine whether it is a palindrome number:

# 输入一个5位数，判断它是否是回文数：
a = int(input(" 请输入一个5位整数："))
s = str(a)
if s[0] == s[-1] and s[1] == s[-2]:
    print(" %d 是一个回文数！" % a)
else:
    print(" %d 不是一个回文数！" % a)

· Determine whether any integer is a palindrome number:

n = int(input('请输入一个整数：'))
s = str(n)
f = True
for i in range(len(s)//2):
    if s[i] != s[-1-i]:
        f = False
        break
if f:
    print('%d 是一个回文数' % n)
else:
    print('%d 不是一个回文数' % n)

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