update readme

Author: hogan-tech

.github/Question List.txt

@@ -7,4 +7,5 @@
 2610-convert-an-array-into-a-2d-array-with-conditions python medium
 2125-number-of-laser-beams-in-a-bank python medium
 2870-minimum-number-of-operations-to-make-array-empty python medium
-0300-longest-increasing-subsequence python medium
+0300-longest-increasing-subsequence python medium
+0446-arithmetic-slices-ii-subsequence python hard

README.md

@@ -182,6 +182,7 @@ The solutions are organized as follows:
 | 0416 | [Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/)                                                                             | [Python](./0416-partition-equal-subset-sum/0416-partition-equal-subset-sum.py)                                                                                                                                                               | [Medium](./0416-partition-equal-subset-sum/README.md)                                     |
 | 0438 | [Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/)                                                                       | [Python](./0438-find-all-anagrams-in-a-string/0438-find-all-anagrams-in-a-string.py)                                                                                                                                                         | [Medium](./0438-find-all-anagrams-in-a-string/README.md)                                  |
 | 0439 | [Ternary Expression Parser](https://leetcode.com/problems/ternary-expression-parser/)                                                                               | [Python](./0439-ternary-expression-parser/0439-ternary-expression-parser.py)                                                                                                                                                                 | [Medium](./0439-ternary-expression-parser/README.md)                                      |
+| 0446 | [Arithmetic Slices II - Subsequence](https://leetcode.com/problems/arithmetic-slices-ii-subsequence/)                                                               | [Python](./0446-arithmetic-slices-ii-subsequence/0446-arithmetic-slices-ii-subsequence.py)                                                                                                                                                   | [Hard](./0446-arithmetic-slices-ii-subsequence/README.md)                                 |
 | 0455 | [Assign Cookies](https://leetcode.com/problems/assign-cookies/)                                                                                                     | [Python](./0455-assign-cookies/0455-assign-cookies.py)                                                                                                                                                                                       | [Easy](./0455-assign-cookies/README.md)                                                   |
 | 0456 | [132 Pattern](https://leetcode.com/problems/132-pattern/)                                                                                                           | [Python](./0456-132-pattern/0456-132-pattern.py)                                                                                                                                                                                             | [Medium](./0456-132-pattern/README.md)                                                    |
 | 0458 | [Poor Pigs](https://leetcode.com/problems/poor-pigs/)                                                                                                               | [Python](./0458-poor-pigs/0458-poor-pigs.py)                                                                                                                                                                                                 | [Hard](./0458-poor-pigs/README.md)                                                        |