Update README.md

kamyu104 · web-flow · commit 81620cab35ae · 2016-08-03T22:57:06.000+08:00
diff --git a/README.md b/README.md
@@ -491,7 +491,7 @@ I'll keep updating for full summary and better solutions. Stay tuned for updates
 355| [Design Twitter](https://leetcode.com/problems/design-twitter/) | [C++](./C++/design-twitter.cpp) [Python](./Python/design-twitter.py) | _O(klogu)_| _O(t + f)_| Hard | LintCode | Heap |
 359| [Logger Rate Limiter](https://leetcode.com/problems/logger-rate-limiter/) | [C++](./C++/logger-rate-limiter.cpp) [Python](./Python/logger-rate-limiter.py) | _O(1), amortized_ | _O(k)_| Easy |📖| Deque |
 362| [Design Hit Counter](https://leetcode.com/problems/design-hit-counter/) | [C++](./C++/design-hit-counter.cpp) [Python](./Python/design-hit-counter.py) | _O(1), amortized_ | _O(k)_| Medium |📖| Deque |
-379| [Design Phone Directory](https://leetcode.com/problems/design-phone-directory/) | [C++](./C++/design-phone-directory.cpp) [Python](./Python/design-phone-directory.py) | _O(1), amortized_ | _O(n)_| Medium |📖| |
+379| [Design Phone Directory](https://leetcode.com/problems/design-phone-directory/) | [C++](./C++/design-phone-directory.cpp) [Python](./Python/design-phone-directory.py) | _O(1)_ | _O(n)_| Medium |📖| |
 
 ## SQL
   #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note
