What are some advanced techniques to solve the Two Sum problem?

What are some advanced techniques to solve the Two Sum problem?

There are several advanced techniques to solve the Two Sum problem, such as using hash maps, sorting with two pointers, and binary search. Would you like to explore one of these methods in detail?

Can you explain how to use hash maps for this problem?

Sure! Using a hash map allows you to store the numbers you've seen so far and their indices. As you iterate through the array, you can check if the complement (target - current number) exists in the hash map. If it does, you've found your solution!

What is the time complexity of this approach?

The time complexity of the hash map approach is O(n), where n is the number of elements in the array. This is because you traverse the array once and perform constant time operations for each element.

Are there any other efficient methods?

Yes, another efficient method is the two-pointer technique, which works well if the array is sorted. You can start with one pointer at the beginning and another at the end, adjusting them based on the sum compared to the target.