Teacher: In this task, you are given two strings A,B. Find the longer of the two lists, convert it to lowercase, and return all the unique alphabets used in it. The two input strings are never equal.
Teacher: Now, understand the problem? If you are still confused, see the following example:
JkbloNUq, nYblowj
Solution: b, j, k, l, n, o, q, u
Reason: Here, 'JkbloNUq' is the longer string among the two input strings. Lowercasing it and finding all unique alphabets gives 'b, j, k, l, n, o, q, u'.

Now, solve this instance: VApwOzTgZmxbhrTyqQBGUPYFSmAEUVX, FwCbBwcKrqaLlbhrTyqQBGUPYFSmeMevvmUaxaCK
Student:
a, b, c, e, f, g, h, k, l, m, p, q, r, s, t, u, v, w, x, y