2 Sum - Pair Sum Closest to Target

In this video, we will learn how to find the pair with the sum closest to a given target in an array. The task is to find a pair of integers in a sorted array whose sum is closest to the target. If multiple pairs have the same sum, we return the one with the maximum absolute difference between its elements. The solution explores three approaches: a naive approach using nested loops, a binary search technique for optimized performance, and a two-pointer technique that works efficiently by sorting the array first. We’ll see step-by-step how each approach works and the corresponding code implementation.

Using the two-pointer technique, we efficiently find the pair with the closest sum by iterating through the sorted array with two pointers—one pointing to the beginning and the other pointing to the end of the array. This approach ensures we quickly find the pair closest to the target sum. The program outputs the closest pair, and handles cases where the array has only one element, returning an empty array in such cases. With time complexity O(n), this method offers a highly optimized solution for finding the pair sum closest to the target.

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