Update README.md

Author: mjebrahimi

README.md

@@ -70,6 +70,10 @@ If you find this repository useful and like it, why not give it a star? if not,
 
 All the benchmarks are visualized using [BenchmarkDotNetVisualizer](https://github.com/mjebrahimi/BenchmarkDotNetVisualizer).
 
+## Todo
+
+- [ ] Add benchmarks for other operations such as **Add**, **Insert**, **Remove**, and **Update**.
+
 ## Useful Resources
 
 - [.NET Big-O Algorithm Complexity Cheat Sheet](https://github.com/RehanSaeed/.NET-Big-O-Algorithm-Complexity-Cheat-Sheet)