diff --git a/.all-contributorsrc b/.all-contributorsrc
index ffe698d84..ca9e4c8e0 100644
--- a/.all-contributorsrc
+++ b/.all-contributorsrc
@@ -291,6 +291,15 @@
         "code"
       ]
     },
+    {
+      "login": "hoangnam2261",
+      "name": "hoangnam2261",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/31692990?v=4",
+      "profile": "https://github.com/hoangnam2261",
+      "contributions": [
+        "code"
+      ]
+    },
     {
       "login": "jarpit96",
       "name": "Arpit Jain",
diff --git a/README.md b/README.md
index c59bfac02..b10ea2a59 100644
--- a/README.md
+++ b/README.md
@@ -166,6 +166,7 @@ This project is licensed under the terms of the MIT license.
   </tr>
     <td align="center"><a href="http://mitchell-irvin.com"><img src="https://avatars0.githubusercontent.com/u/16233245?v=4" width="100px;" alt=""/><br /><sub><b>Mitchell Irvin</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=mitchellirvin" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/jarpit96"><img src="https://avatars2.githubusercontent.com/u/10098713?v=4" width="100px;" alt=""/><br /><sub><b>Arpit Jain</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=jarpit96" title="Code">💻</a></td>
+    <td align="center"><a href="https://github.com/hoangnam2261"><img src="https://avatars2.githubusercontent.com/u/31692990?v=4" width="100px;" alt=""/><br /><sub><b>hoangnam2261</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=hoangnam2261" title="Code">💻</a></td>
   <tr>
     <td align="center"><a href="https://github.com/kirill-vlasov"><img src="https://avatars3.githubusercontent.com/u/16112495?v=4" width="100px;" alt=""/><br /><sub><b>Kirill Vlasov</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=kirill-vlasov" title="Code">💻</a></td>
     <td align="center"><a href="http://joningi.net"><img src="https://avatars2.githubusercontent.com/u/6115148?v=4" width="100px;" alt=""/><br /><sub><b>Jón Ingi Sveinbjörnsson</b></sub></a><br /><a href="https://github.com/iluwatar/java-design-patterns/commits?author=joningiwork" title="Code">💻</a></td>