public class Solution
extends Object
1092 - Shortest Common Supersequence\.
Hard
Given two strings `str1` and `str2`, return _the shortest string that has both_ `str1` _and_ `str2` _as **subsequences**_. If there are multiple valid strings, return **any** of them.
A string `s` is a **subsequence** of string `t` if deleting some number of characters from `t` (possibly `0`) results in the string `s`.
**Example 1:**
**Input:** str1 = "abac", str2 = "cab"
**Output:** "cabac"
**Explanation:**
str1 = "abac" is a subsequence of "cabac" because we can delete the first "c".
str2 = "cab" is a subsequence of "cabac" because we can delete the last "ac".
The answer provided is the shortest such string that satisfies these properties.
**Example 2:**
**Input:** str1 = "aaaaaaaa", str2 = "aaaaaaaa"
**Output:** "aaaaaaaa"
**Constraints:**
* `1 <= str1.length, str2.length <= 1000`
* `str1` and `str2` consist of lowercase English letters.