Added while loop factorial

Maths/WhileLoopFactorial.js

@@ -0,0 +1,20 @@
+/*
+    author: Theepag
+ */
+const factorialize = (num) => {
+    // Step 1. variable result to store num
+    let result = num;
+    // If num = 0 OR 1, the factorial will return 1
+    if (num === 0 || num === 1) 
+      return 1; 
+    // Step 2. WHILE loop 
+    while (num > 1) { 
+      num--; // decrement 1 at each iteration
+      result = result * num; // or result = result * num;
+    }
+    // Step 3. Return the factorial
+    return result;
+}
+//test
+console.log(factorialize(5));
+console.log(factorialize(4));