Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.
Example 1:
Input: 121 Output: true
Example 2:
Input: -121 Output: false Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
Example 3:
Input: 10 Output: false Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
Follow up:
Coud you solve it without converting the integer to a string?
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JPMorgan, Amazon, Bloomberg, Adobe, Microsoft, Facebook, Yahoo, Tencent
Related Topics:
Math
Similar Questions:
// OJ: https://leetcode.com/problems/palindrome-number/
// Author: github.com/lzl124631x
// Time: O(N)
// Space: O(1)
class Solution {
public:
bool isPalindrome(int x) {
if (x < 0) return false;
long long a = x, b = 0;
while (x) {
b = b * 10 + x % 10;
x /= 10;
}
return a == b;
}
};