Get factorial number

Author: edignot

src/factorial/factorial.js

@@ -0,0 +1,19 @@
+// Problem: return a factorial number of a given positive integer
+
+// Loop approach: 
+export const getFactorial = (num) => {
+  let result = 1
+  for (let i = 2; i <= num; i++) {
+    result *= i
+  }
+  return result
+}
+
+// Recursive approach:
+export const getFactorialRecursion = (num) => {
+  if (num > 1) {
+    return num * getFactorialRecursion(num - 1)
+  } else {
+    return 1
+  }
+}

src/factorial/factorial.test.js

@@ -0,0 +1,19 @@
+import { getFactorial, getFactorialRecursion } from "./factorial";
+
+describe("Factorial number", () => {
+    test("Return factorial of 3", () => {
+        expect(getFactorial(3)).toBe(6);
+    });
+    test("Return factorial of 6", () => {
+        expect(getFactorial(6)).toBe(720);
+    });
+});
+
+describe("Factorial number | Recursive approach", () => {
+    test("Return factorial of 3", () => {
+        expect(getFactorialRecursion(3)).toBe(6);
+    });
+    test("Return factorial of 6", () => {
+        expect(getFactorialRecursion(6)).toBe(720);
+    });
+});

src/fibonacci-sequence/fibonacci-sequence.js

@@ -2,7 +2,6 @@
 // Details: e.g. fibonacci sequence: 1,1,2,3,5,8,13,21...
 
 // Time complexity: O(n)
-
 const getFibonacciEl = (i) => {
     const fibonacciArr = [1, 1];
     for (let x = 1; x < i; x++) {