Check if a Number is a Palindrome

📌 Definition:

📖 Detailed Explanation:

Reverse the number arithmetically (or half of it) and compare to the original. Negative numbers are not palindromes (the minus sign). You can avoid string conversion entirely by reversing digits with %10 and /10.

💻 Solutions:

• Java
• JavaScript
• Python

public static boolean isPalindrome(int n) {
    if (n < 0) return false;
    int original = n, rev = 0;
    while (n != 0) { rev = rev * 10 + n % 10; n /= 10; }
    return rev == original;
}

function isPalindrome(n) {
  if (n < 0) return false;
  const s = String(n);
  return s === s.split('').reverse().join('');
}

def is_palindrome(n):
    if n < 0:
        return False
    return str(n) == str(n)[::-1]

🔑 Key Points:

• Negatives are not palindromes
• Reverse digits with %10 // /10, compare
• String reverse is a valid alternative
• Reversing only half avoids overflow

🌍 Real-World Example: