let s = n.toString();

  let p = true;

  for (let i = 0; i < s.length; i++) {

    if (s[i] != s[s.length - 1 - i]) {

      p = false;

    }

  }

  return p;

}

​

let highest = 0;

​

for (let x = 999; x >= 900; x--) {

  for (let y = 999; y >= 900; y--) {

    let p = x * y;

    if (palindrome(p) && p > highest) {

      highest = p;

    }

  }

}

​

console.log(highest);