What are some examples of the two-sum problem?

Can you explain the two-sum problem with some examples?

Sure! The two-sum problem involves finding two numbers in an array that add up to a specific target. For example, given the array [2, 7, 11, 15] and a target of 9, the numbers 2 and 7 add up to 9.

What if the array is [3, 2, 4] and the target is 6?

In that case, the numbers 2 and 4 from the array [3, 2, 4] add up to the target of 6.

Can you provide a code example for solving the two-sum problem?

Certainly! Here's a simple Python code snippet:

def two_sum(nums, target):
    num_map = {}
    for i, num in enumerate(nums):
        complement = target - num
        if complement in num_map:
            return [num_map[complement], i]
        num_map[num] = i

This function returns the indices of the two numbers that add up to the target.

Are there any variations of the two-sum problem?

Yes, variations include the three-sum problem, where you find three numbers that add up to a target, and the k-sum problem, which generalizes this to k numbers.