refactor calculatePossibleRangeSize to be more readable

index.html

@@ -132,7 +132,7 @@
             const divisors = [];
             for (let i = 1; i <= num; i++) {
                 const quotient = num / i;
-                if (num % i === 0 || (quotient % 0.5 === 0 && quotient !== Math.floor(quotient))) {
+                if (Number.isInteger(quotient) || (quotient % 0.5 === 0 && !Number.isInteger(quotient))) {
                     divisors.push(i);
                 }
             }