9. Palindrome Number

Description

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?

Answer

Time complexity : O(\log_{10}(n))O(log
​10
​​ (n)). We divided the input by 10 for every iteration, so the time complexity is O(\log_{10}(n))O(log
​10
​​ (n))

Space complexity : O(1)O(1).

package main

import "fmt"

func isPalindrome(x int) bool {
    if x < 0 {
        return false
    }

    var temp int
    var tempsource int = x
    for x != 0 {
        temp = temp*10 + x%10
        x = x / 10

    }
    return temp == tempsource

}

func main() {
    fmt.Println(isPalindrome(101))
}