Create multiply.js (#140)

Multiply Two numbers using Bit-wise Operator.

src/algorithms/math/bits/multiply.js

@@ -0,0 +1,14 @@
+/**
+ * @param {number, number} 
+ * @return {number} 
+ */
+export default function multiply(number1, number2) {
+  var c = 0, result = 0; 
+  while(number2){
+    if(number2&1)
+        result += (number1 << c);
+    c += 1;
+    number2 >>= 1;
+  }
+  return result;
+}