Checking for an isogram?

I am curently making a word game in BP’s. and i would like to check if the word the player has input is an isogram (word with no repeating letters). I have one working in C++, but i cant find any node that seems to be equivilent to the C++ TMap. Im doing this in blueprints because i am much better at blueprints than i am at C++.

;-- C++ code

Whats going on in the code:
Set words of length 0 or 1 to an isogram by default (i know how to do this just fine)
then it goes through each letter in the player guess, putting them in a map and checking if its a doubled up letter as it goes.
If no letters are doubled up it will return true: is an isogram
If it finds a doubled up letter it stops right then and returns false, not an isogram

This should work.

well hello and thanks again haha