Day 01: LeetCode 9 [Palindrome]
Problem Description:
Given an integer x, return true if x is a palindrome, and false otherwise.
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: -2^31 <= x <= 2^31 - 1
Link to LeetCode Problem:
https://leetcode.com/problems/palindrome-number/
My Thought Process:
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Palindromes are defined for positive values. If x is negative, immediately return false.
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Reversing Digits of x: > Creating a copy of x to avoid modification. > Using a variable revNum to store the reversed number. > Loop through digits of x one by one: > Extracting the last digit using modulo (%). > Appending the digit to the front of revNum by multiplying revNum by 10 and adding the digit. > Removing the last digit from x using integer division (/). > Comparing Original and Reversed Numbers:
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Comparing revNum with the original x. If they are equal, x is a palindrome (return true). Otherwise, x is not a palindrome (return false).
