Hello, and welcome back! Are you ready for a new challenge? In this unit, we're exploring an interesting task using Kotlin's powerful map capabilities. We'll be focusing on parsing complex strings into nested maps and updating them. This is a common requirement in many real-world tasks, making our session particularly practical — just the way you like it!

This task involves transforming a given string into a nested map and updating a specific key-value pair within that map using Kotlin. The input string will take the form "Key1=Value1,Key2=Value2,...". When a part of the value is another key-value string, we create a nested map.

For example, the string "A1=B1,C1={D1=E1,F1=G1},I1=J1" should be transformed into the following nested map:

Your function should parse this string into the above nested map, then update the value of the nested key F1 from G1 to another value, say NewValue. The function should ultimately return the updated map.

First, set up the function and necessary variables in Kotlin:

Next, handle the opening and closing braces. If an inner map is encountered, set the flag and prepare to parse it:

Handle parsing key-value pairs in the outer map:

Handle parsing key-value pairs inside the inner map:

Now that we have the parsed map, we can move into the final phase of the task: updating a specific key-value pair. Here’s the function to update a value in the nested map:

Finally, we put everything together in one function to parse the string and update the value:

Well done! You've completed an intensive hands-on session dealing with complex strings and nested maps in Kotlin. This type of task mirrors real-life scenarios where you process complex data and make updates based on specific criteria.

Now it's your turn to reinforce what you've learned in this unit. Try practicing with different strings and attempting to update various key-value pairs. With practice, you'll be able to apply these coding strategies to a wide range of problems. Happy coding!