Merge pull request knaxus#94 from iamvalentin23/master

Added factorial problem and solution

Author: ashokdey

src/_Problems_/factorial/index.js

@@ -0,0 +1,8 @@
+function factorial(num) {
+    if (num === 1) return num;
+    else return num * factorial(num - 1);  
+}
+
+module.exports = {
+    factorial,
+  };

src/_Problems_/factorial/index.test.js

@@ -0,0 +1,15 @@
+const { factorial } = require('.');
+
+describe('Factorial', () => {
+  it('Should return 24', () => {
+    expect(factorial(4)).toEqual(24);
+  });
+
+  it('Should return 1', () => {
+    expect(factorial(1)).toEqual(1);
+  });
+
+  it('Should return 120', () => {
+    expect(factorial(5)).toEqual(120);
+  });
+});