Question Link
https://leetcode.com/problems/two-sum/
Solution 1 - Brute Force
https://github.com/anandvardhandas/LeetCodeEasyQuestions/blob/main/1TwoSum_BruteForce.cs
Solution 2 - Optimized - Dictionary or Hashtable O(n)
https://github.com/anandvardhandas/LeetCodeEasyQuestions/blob/main/1TwoSum_HashTableDictionary.cs