Solving LeetCode problem 136 in APL (Single Number)

In this short video we solve a LeetCode problem in APL:

[Yaketycast]

Nicely done with the linear solution at the end XD

[goncaloteixeira]

Damn. when you think that you could probably understand what a program is doing in most languages and then you find APL.
I need to learn these hahaha.
Awesome video

[foxoninetails_]

In J, you can do this easily with -/@/:~ (sort, then reduce with subtraction), although I'm not sure of the time complexity. You can even remove the @ in some situations, though it's needed if parenthesized or named as a point-free defn, so the whole construction isn't recognized erroneously as a hook.