Given two strings s and t, return the shortest substring of s such that every character in t, including duplicates, is present in the substring. If such a substring does not exist, return an empty string "".
You may assume that the correct output is always unique.
Example 1:
Input: s = "OUZODYXAZV", t = "XYZ"
Output: "YXAZ"Explanation: "YXAZ" is the shortest substring that includes "X", "Y", and "Z" from string t.
Example 2:
Input: s = "xyz", t = "xyz"
Output: "xyz"Example 3:
Input: s = "x", t = "xy"
Output: ""Constraints:
1 <= s.length <= 10001 <= t.length <= 1000s and t consist of uppercase and lowercase English letters.