###### tags: `Leetcode` `easy` `math` `python` `c++`
# 9. Palindrome Number
## [題目來源:]https://leetcode.com/problems/palindrome-number/
## 題目:
Given an integer x, return true if x is palindrome integer.
An integer is a palindrome when it reads the same backward as forward.
For example, 121 is a palindrome while 123 is not.
## 解題想法:
反轉: 逐一取餘數再*10還原
# Python:
``` python=
class Solution(object):
def isPalindrome(self, x):
"""
:type x: int
:rtype: bool
"""
if x<0:
return False
y=x
res=0
while y>0:
tmp=y%10
res=(res*10)+tmp
y=y//10
return x==res
if __name__ == '__main__':
result = Solution()
print(result.isPalindrome(121))
```
## C++:
``` cpp=
#include <iostream>
using namespace std;
class Solution
{
public:
bool isPalindrome(int x)
{
if (x < 0)
return false;
long int x_reverse = 0;
int x_original = x;
while (x)
{
x_reverse = x_reverse * 10 + x % 10;
x /= 10;
}
return x_reverse == x_original;
}
};
int main()
{
Solution res;
int target = 121;
cout << res.isPalindrome(target) << endl;
return 0;
}
```