-- We shall say that an n-digit number is pandigital if it makes use of all the
-- digits 1 to n exactly once. For example, 2143 is a 4-digit pandigital and is
-- also prime.
--
-- What is the largest n-digit pandigital prime that exists?

import Euler

pandigitals = map fromDigits $ go 9
   where go 0 = []; go n = reverse (sort (permutations [1..n])) ++ go (n-1)

main = print $ head $ filter isPrime pandigitals