Update euclideanAlgorithm.js (trekhleb#207)

Method 2 is easy to evaluate or understand without using recursion stack!

src/algorithms/math/euclidean-algorithm/euclideanAlgorithm.js

@@ -3,9 +3,23 @@
  * @param {number} originalB
  * @return {number}
  */
+
+/*Method 1: A bit Complex to understand*/
 export default function euclideanAlgorithm(originalA, originalB) {
   const a = Math.abs(originalA);
   const b = Math.abs(originalB);
 
   return (b === 0) ? a : euclideanAlgorithm(b, a % b);
 }
+
+/*Method 2: Easy to evaluate*/
+export default function euclideanAlgorithm2(originalA, originalB) {
+  const a = Math.abs(originalA);
+  const b = Math.abs(originalB);
+
+  while(a != b){
+    [a,b] = a>b : [a-b, b] : [a, b-a]
+  }
+
+  return a || b;
+}