added some additional info to the readme file

Author: jeremymanning

README.md

@@ -4,7 +4,24 @@ Each day (ideally) we'll attempt the daily [leetcode](https://leetcode.com) prob
 
 # Problems we've attempted thus far:
 
-| Date        | Problem                                                                                 | Link to notes                                                                                             |
-|-------------|-----------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------|
-| July 1, 2024 | [350](https://leetcode.com/problems/intersection-of-two-arrays-ii/) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/350) |
-| July 2, 2024 | [1509](https://leetcode.com/problems/minimum-difference-between-largest-and-smallest-value-in-three-moves/) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/1509) |
+| Date         | Problem                                                                                                     | Link to notes                                                                                             | Difficulty |
+|--------------|-------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------|------------|
+| July 1, 2024 | [350](https://leetcode.com/problems/intersection-of-two-arrays-ii/)                                         | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/350)                     | Easy       |
+| July 2, 2024 | [1509](https://leetcode.com/problems/minimum-difference-between-largest-and-smallest-value-in-three-moves/) | [Click here](https://github.com/ContextLab/leetcode-solutions/tree/main/problems/1509)                    | Medium     |
+
+# Join our discussion!
+
+If you're a member of [our lab](https://www.context-lab.com/) and/or a [Dartmouth](https://home.dartmouth.edu/) community member, feel free to join our [Slack channel](https://app.slack.com/client/EQ19QMD6Z/C0753BB4MC5) to discuss daily leetcode problems!
+
+# Submit your own notes and/or solution(s)
+
+1. Start by [forking](https://github.com/ContextLab/leetcode-solutions/fork) this repository.
+2. In your fork, navigate to the [problems](https://github.com/ContextLab/leetcode-solutions/new/main/problems) folder and click the **Add file** button on the right.  Choose the **Create new file** option:
+  - File name: `leetcode-solutions/problems/<PROBLEM NUMBER>/<your name>.md` (where you should replace `<PROBLEM NUMBER>` with the leetcode problem ID code, and `<your name>` with your first name, in lowercase letters.  E.g., [Jeremy](https://www.context-lab.com/people)'s solution to problem 350 would be named `leetcode-solutions/blob/main/problems/350/jeremy.md`
+  - Contents: Any format is fine, but we suggest starting with our [template file](https://github.com/ContextLab/leetcode-solutions/blob/main/problems/template.md).  Then add your notes/solution as you solve the problem!  Make sure to commit your changes (and it's fine to make multiple commits as you're working on the problem).
+3. Once you've added your file, start a [pull request](https://github.com/ContextLab/leetcode-solutions/pulls) to add it into the ContextLab fork so that others can see how you approached the problem.
+4. Also make sure that the problem has been added to the [table](https://github.com/ContextLab/leetcode-solutions#problems-weve-attempted-thus-far).  If you're the first one to work on a problem, you'll need to add a row for it.  Problems should be listed in chronological order from top (earliest) to bottom (latest).
+
+# Question? Comments? Concerns?
+
+You can work through problems "live" in our [Slack channel](https://app.slack.com/client/EQ19QMD6Z/C0753BB4MC5).  To make comments on a specific solution, make suggestions for this repository in general, etc., consider filing an [issue](https://github.com/ContextLab/leetcode-solutions/issues).