Palindrome Number Problem
Description
LeetCode Problem 9.
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 palindrome while 123 is not.
Example 1:
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Input: x = 121
Output: true
Example 2:
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Input: x = -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:
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Input: x = 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
Example 4:
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Input: x = -101
Output: false
Constraints:
- -2^31 <= x <= 2^31 - 1
Sample C++ Code
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class Solution {
public:
bool isPalindrome(int x) {
if (x<0|| (x!=0 &&x%10==0)) return false;
int sum=0;
while (x>sum)
{
sum = sum*10+x%10;
x = x/10;
}
return (x==sum)||(x==sum/10);
}
};