We can shift a string by shifting each of its letters to its successive letter. For example, "abc" can be shifted to be "bcd". We can keep shifting the string to form a sequence. For example, we can keep shifting "abc" to form the sequence: "abc" -> "bcd" -> ... -> "xyz". Given an array of strings strings, group all strings[i] that belong to the same shifting sequence. You may return the answer in any order. Example 1: Input: strings = ["abc","bcd","acef","xyz","az","ba","a","z"] Output: [["acef"],["a","z"],["abc","bcd","xyz"],["az","ba"]] Example 2: Input: strings = ["a"] Output: [["a"]] Constraints: 1 <= strings.length <= 200 1 <= strings[i].length <= 50 strings[i] consists of lowercase English letters.