Merging two triplets takes the maximum in each position. Return whether some sequence of merges can produce the target.
Before you code
Maximums only grow. A triplet with any value above the target's in that position can never be used. Every other triplet can be merged without harm.
Hints
- Skip triplets that exceed the target anywhere.
- Merge all the rest, or just record which target positions some safe triplet matches exactly.
- The answer is whether all three positions are matched.
Production & complexity notes
When solving Merge triplets to form target triplet on LeetCode (medium), always state your loop or recursion invariant before writing code. Verify how your chosen data structure behaves on degenerate inputs (single-element inputs, all-duplicate keys, strictly monotonic sequences, or maximum constraint sizes up to $10^5$ elements). In production interviews, pair your implementation with an explicit time and auxiliary space complexity proof, explain why alternative brute-force approaches violate the latency budget, and trace how cache locality and memory allocation overhead affect wall-clock throughput on real hardware. Review the step-by-step memory trace in Exchange arguments to reinforce the underlying pattern.
What it practices
Arguing that a greedy choice never hurts, from Exchange arguments.