Digitaldrome

In this challenge, you have to establish if the digits of a given number form a sequence (ascending or descending).

Given an integer n, implement a function that returns a string:

• "Metadrome" if the digits of n form an ascending sequence without repeating digits.
• "Plaindrome" if the digits of n form an ascending sequence with repeating digits.
• "Katadrome" if the digits of n form a descending sequence without repeating digits.
• "Nialpdrome" if the digits of n form a descending sequence with repeating digits.
• "Repdrome" if n contains a single repeating digit.
• "Nondrome" if none of the above conditions is true.

Examples

digitaldrome(1357) ➞ "Metadrome"
# Ascending sequence without repeating digits

digitaldrome(12344) ➞ "Plaindrome"
# Ascending sequence with repeating digits

digitaldrome(7531) ➞ "Katadrome"
# Descending sequence without repeating digits

digitaldrome(9874441) ➞ "Nialpdrome"
# Descending sequence with  repeating digits

digitaldrome(666) ➞ "Repdrome"
# There's only a single repeating digit

digitaldrome(1985) ➞ "Nondrome"
# This is not a sequence

Notes

• Any given n will be a positive integer.
• The word "drome" comes from the Greek suffix for "run", while "kata" and "meta" are the prefixes for "down" (or "into") and "after" (or "through").