Editing ray

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// A palindromic number reads the same both ways. The largest palindrome made // from the product of two 2-digit numbers is 9009 = 91 x 99. // Find the largest palindrome made from the product of two 3-digit numbers. (function euler004() { // start with the largest number from two 3-digit numbers var n = 999 * 999; var nStr; var nStrReversed; var sqrt; var divisor; while (n > 200000) { // check if n is a palindrome // convert to string nStr = n + ''; // reverse string nStrReversed = nStr.split('').reverse().join(''); // if they are identical, then n is a palindrome if (nStr === nStrReversed) { // find the sqrt // one of the factors has to be less than the sqrt // so this reduces the number of iterations needed sqrt = Math.sqrt(n); // make it an integer divisor = Math.floor(sqrt); // while n / divisor leaves a remainder // and the divisor greater than 3-digits // and the other factor less than 4-digits while (n % divisor !== 0 && divisor >= 100 && n / divisor <= 999) { // reduce divisor by 1 divisor--; } // if n / divisor leaves no remainder // and the divisor is greater than 3-digits // and thh other factor is less than 4-digits if (n % divisor === 0 && divisor >= 100 && n / divisor <= 999) { // return the answer console.log(n); return n; } } n--; } }());

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