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.
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Question: TArRiBAAXWYAdtJzDRgmvK, HOEdDYxRiBAAXWYAdtJzidCBfCxg

Answer: a, b, c, d, e, f, g, h, i, j, o, r, t, w, x, y, z


Question: BgWNZsW, iZWNls

Answer: b, g, n, s, w, z


Question: lJgNMtgABjIYeqjsYCebSTnKPPoquL, PdLEAJIYeqjsYCebSpR

Answer:
a, b, c, e, g, i, j, k, l, m, n, o, p, q, s, t, u, y