#PANDIGITAL NUMBERS

A number of length n is pandigital if it makes use of all the digits 1 to n exactly once.

- The number `15234` is 1 through 5 pandigital.

- The number `333` is not pandigital.

- The number `0` is not pandigital.

- The number `987654321` is pandigital. 

###DIRECTIONS
Write a function that checks if a number is pandigital.