Add Generate Random Integers as a javascript til

javascript/generate-random-integers.md

@@ -0,0 +1,30 @@
+# Generate Random Integers
+
+JavaScript's `Math` module has a built-in `random` function.
+
+```javascript
+> Math.random();
+0.4663311937101857
+```
+
+It can be used to generate random floats between 0 and 1.
+
+If you want integers, though, you're going to have to build your own function.
+
+```javascript
+function getRandomInt(max) {
+  return Math.floor(Math.random() * Math.floor(max));
+}
+
+> getRandomInt(10);
+1
+> getRandomInt(10);
+7
+> getRandomInt(10);
+2
+```
+
+This function allows you to randomly generate numbers between `0` (inclusive)
+and `max`, a number you specify (exclusive).
+
+[source](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random)