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Optimized 3-Sum
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Optimized 3-Sum

HardPython

Problem

Solve the 3-Sum problem, optimizing your solution to run in O(N^2) time complexity.

Implement def three_sum(nums):. Given a list of integers, return every unique triplet [a, b, c] such that a + b + c == 0. The result must not contain duplicate triplets, and each triplet must be sorted in nondecreasing order. Return an empty list when no valid triplet exists.

Constraints

  • 3 <= nums.length <= 3000
  • -10^5 <= nums[i] <= 10^5
  • Triplets must contain values from distinct array positions
  • The output must contain unique triplets only

Function Signature

def three_sum(nums):
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