ELI5: 3sum leetcode
// explanation
What is the 3Sum LeetCode problem?
The 3Sum problem asks you to find all groups of three different numbers in a list that add up to zero [1]. It's like finding three puzzle pieces that fit together perfectly to make a complete picture.
Why is it tricky?
You can't just try every possible group of three numbers because that would take too long with a big list [3]. You need to be smart about which combinations you check.
What's the trick to solving it?
First, sort your numbers from smallest to biggest [2]. Then for each number, use two pointers (like fingers) to find two other numbers that add up with it to make zero [2]. This way you skip checking combinations you've already seen.
Why do people find it hard?
Even experienced programmers sometimes struggle with this because you have to think about sorting first and managing duplicate numbers carefully [4].
// sources
Can you solve this real interview question? 3Sum - Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i !
Feb 16, 2023 ... Solution: def threeSum(self, nums: List[int]) -> List[List[int]]: result = [] nums.sort() for i, a in enumerate(nums): if i > 0 and a == nums
The most direct way to solve the 3Sum problem is by using three nested loops to consider every possible combination of three distinct elements. For each such ...
Oct 10, 2018 ... I'm a Junior but I could only come up with the “easy brute force solution” on leetcode. Should every good programmer be expected to know how to ...
Apr 15, 2024 ... This comprehensive guide aims to fully equip you with the knowledge to tackle the 3Sum problem efficiently, ensuring you stand out in your next coding ...
Video by NeetCode
Video by Nikhil Lohia
Video by Greg Hogg
