Question
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.
Example 1:
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| Input: x = 121
Output: true
Explanation: 121 reads as 121 from left to right and from right to left.
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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.
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Example 3:
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| Input: x = 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
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My Answer
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| var isPalindrome = function(x) {
const strs = (x + '').split('')
const reverseStrs = [...strs].reverse()
return strs.every((str, index) => str === reverseStrs[index])
};
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Best Answer
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| var isPalindrome = function(x) {
if (x < 0) return false
let rev = 0
for(let i = x; i >= 1; i = Math.floor(i/10)) rev = rev*10 + i%10
return rev === x
};
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