Master this problem using the Two Pointers pattern.
When approaching 3Sum, look for key problem signals that suggest using the Two Pointers pattern. Focus on reducing redundant iterations, maintaining state invariant, and optimizing space-time complexity.
Key Invariant
Maintain optimal range bounds or hash frequency state during traversal.
Expected Complexity
Time: O(N) or O(N log N) | Space: O(1) to O(N)
Study Resource
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