Return if a number is a palindrome.
function isPalindrome(n) {
if (n < 0) return false;
let str = String(n);
for (let i = 0; i < str.length / 2; i++) {
if (str[i] !== str[str.length - 1 - i]) return false;
}
return true;
}
const x = isPalindrome(111);
const y = isPalindrome(122);
const z = isPalindrome(-121);
console.log(x);
console.log(y);
console.log(z);