Given two strings, original and check, return the shortest substring of original that contains every character in check, including duplicates. If multiple valid substrings have the same length, return the lexicographically smallest one.
Parameters
original: The source string.
check: The required characters.
Result
The minimum valid window in original.
Examples
Example 1
Input: original = "cdbaebaecd", check = "abc"
Output: baec
Explanation: Both cdba and baec are valid windows of length 4. We return baec because it is lexicographically smaller.
Constraints
1 <= len(check), len(original) <= 10^5
original and check contain only uppercase and lowercase English letters. Characters are case-sensitive.