Given a list of sorted characters letters containing only lowercase letters, and given a target letter target, find the smallest element in the list that is larger than the given target. Letters also wrap around. For example, if the target is target = 'z' and letters = ['a', 'b'], the answer is 'a'. Examples: Input: letters = ["c", "f", "j"] target = "a" Output: "c" Input: letters = ["c", "f", "j"] target = "c" Output: "f" Input: letters = ["c", "f", "j"] target = "d" Output: "f" Input: letters = ["c", "f", "j"] target = "g" Output: "j" Input: letters = ["c", "f", "j"] target = "j" Output: "c" Input: letters = ["c", "f", "j"] target = "k" Output: "c" Note: letters has a length in range [2, 10000]. letters consists of lowercase letters, and contains at least 2 unique letters. target is a lowercase letter.