Update digitize.md

Fixes #1376

snippets/digitize.md

@@ -3,15 +3,17 @@ title: digitize
 tags: math,array,beginner
 ---
 
-Converts a number to an array of digits.
+Converts a number to an array of digits, removing its sign if necessary.
 
+- Use `Math.abs()` to strip the number's sign.
 - Convert the number to a string, using the spread operator (`...`) to build an array.
 - Use `Array.prototype.map()` and `parseInt()` to transform each value to an integer.
 
 ```js
-const digitize = n => [...`${n}`].map(i => parseInt(i));
+const digitize = n => [...`${Math.abs(n)}`].map(i => parseInt(i));
 ```
 
 ```js
 digitize(123); // [1, 2, 3]
-```
+digitize(-123); // [1, 2, 3]
+```