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Minimum Pair Removal: Greedy Array Merge Explained

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Developers face a quirky challenge called minimum pair removal: given an integer array, repeatedly merge the adjacent pair with the smallest sum, replacing it with that sum until the list becomes non‑decreasing. The rule forces a greedy simulation that scans left‑to‑right, picks the leftmost minimal pair, and shrinks the array by one each time.

Take [5, 2, 3, 1]. First scan finds (3, 1) with sum 4, merge to get [5, 2, 4]. The array still unsorted, so next minimal pair is (2, 4) sum 6, yielding [5, 6]. Two operations finish the process. The algorithm runs in O(n²) worst‑case, but n is tiny in typical interview limits.

Such a merge‑style routine mirrors real‑world data consolidation, like combining log entries or reconciling ledger lines to meet ordering constraints. Understanding how to mutate arrays safely—using erase, pop, or splice—is a core skill across C++, Python, and JavaScript. Future challenges may extend this pattern to larger datasets or parallel execution.