Implement a function that extracts all keys from a map and returns them as a sorted list. Return an empty list for null or empty maps.

Examples:

Input: map = {'a': 1, 'c': 3, 'b': 2} Output: ['a', 'b', 'c'] Explanation: The keys 'a', 'b', 'c' are extracted and sorted alphabetically Input: map = {'one': 1, 'two': 2, 'three': 3} Output: ['one', 'three', 'two'] Explanation: The keys 'one', 'three', 'two' are extracted and sorted alphabetically
Apex Code Editor

Welcome to Lightning Challenge!

Create an Account

Sign up to track your progress, earn points, and compete with others. Your solutions will be saved automatically.

Create account

How It Works

  • • Write your solution in the code editor
  • • Connect your Salesforce org to test
  • • Submit to check if your solution passes
  • • Use hints if you get stuck

Note

You can test your code by connecting to Salesforce, but to save your progress and earn points, you'll need to create an account. Your solutions and achievements will be tracked automatically once you're logged in.