Recursion: Case and Index Inverter

Write a recursive function that takes a string input and returns the string in a reversed case and order.

Examples

invert("dLROW YM sI HsEt") ➞ "TeSh iS my worlD"

invert("ytInIUgAsnOc") ➞ "CoNSaGuiNiTY"

invert("step on NO PETS") ➞ "step on NO PETS"

invert("XeLPMoC YTiReTXeD") ➞ "dExtErIty cOmplEx"

Notes

• No empty strings and will neither contain special characters nor punctuation.
• You are expected to solve this challenge using a recursive approach.
• An iterative version of this challenge can be found via this link.