9. Palindrome Number

---

Description

Given an integer , return if is a xtruex
palindrome
, and otherwise.false

 

Example 1:

Input: x = 121
Output: true
Explanation: 121 reads as 121 from left to right and from right to left.
Example 2:

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:

Input: x = 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
 

Constraints:

-231 <= x <= 231 - 1
 

Follow up: Could you solve it without converting the integer to a string?

---

Code

func isPalindrome(x int) bool {
    var ans bool

	if x < 0 {
		return ans
	}

	nums := make([]int, 0)

	for {
		division := x / 10

		if division == 0 {
			nums = append(nums, x)

			break
		}

		lastDigit := x - division*10
		x = division

		nums = append(nums, lastDigit)
	}

	left, right := 0, len(nums)-1

	for {
		if left >= right {
			ans = true

			break
		}

		if nums[left] != nums[right] {
			break
		}

		left += 1
		right -= 1
	}

	return ans
}

 

시간 복잡도는 O(log10(n))입니다. 숫자의 자리수를 절반만큼만 처리하기 때문