Update README.md

Author: kamyu104

README.md

@@ -591,7 +591,7 @@
 0963 | [Minimum Area Rectangle II](https://leetcode.com/problems/minimum-area-rectangle-ii/) | [C++](./C++/minimum-area-rectangle-ii.cpp) [Python](./Python/minimum-area-rectangle-ii.py) | _O(n^2)_ ~ _O(n^3)_ | _O(n^2)_      | Medium         ||
 0970 | [Powerful Integers](https://leetcode.com/problems/powerful-integers/) | [C++](./C++/powerful-integers.cpp) [Python](./Python/powerful-integers.py) | _O((logn)^2)_ | _O(r)_      | Easy         ||
 0972 | [Equal Rational Numbers](https://leetcode.com/problems/equal-rational-numbers/) | [C++](./C++/equal-rational-numbers.cpp) [Python](./Python/equal-rational-numbers.py) | _O(1)_ | _O(1)_      | Hard         ||
-1006 | [Clumsy Factorial](https://leetcode.com/problems/clumsy-factorial/) | [C++](./C++/clumsy-factorial.cpp) [Python](./Python/clumsy-factorial.py) | _O(1)_ | _O(1)_      | Hard         ||
+1006 | [Clumsy Factorial](https://leetcode.com/problems/clumsy-factorial/) | [C++](./C++/clumsy-factorial.cpp) [Python](./Python/clumsy-factorial.py) | _O(1)_ | _O(1)_      | Medium         ||
 
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 |  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note|