Add padNumber

snippets/padNumber.md

@@ -0,0 +1,16 @@
+---
+title: padNumber
+tags: string,math,beginner
+---
+
+Pads a given number to the specified length.
+
+- Use `String.prototype.padStart()` to pad the number to specified length, after converting it to a string.
+
+```js
+const padNumber = (n, l) => `${n}`.padStart(l, '0');
+```
+
+```js
+padNumber(1234, 6); // '001234'
+```