Update README.md

Author: AvinandanBose

README.md

@@ -867,7 +867,7 @@ Greatest Element to Lowest Element.
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- <li><h3><a href= "https://github.com/AvinandanBose/JavaCollectionFramework/blob/main/TreeSetDemo17.java" >Comparator Interface on Tree Set[Example]</a></h3></li>
+<li><h3><a href= "https://github.com/AvinandanBose/JavaCollectionFramework/blob/main/TreeSetDemo17.java" >Comparator Interface on Tree Set[Example]</a></h3></li>
 </ul>
 </ul>
 </ul>