Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s.
A palindrome string is a string that reads the same backward as forward.
Example 1:
Input: s = "aab"
Output: [["a","a","b"],["aa","b"]]
Example 2:
Input: s = "a"
Output: [["a"]]
```
**Constraints:**
+ `1 <= s.length <= 16`
+ `s` contains only lowercase English letters.