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LeetCode Merge Intervals: Optimal Solution Guide

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LeetCode's Merge Intervals problem, number 56 in the Top Interview 150 list, challenges developers to consolidate overlapping time ranges efficiently. The presented solution sorts intervals by start time, then iterates through them to merge where the current interval's end exceeds the next's start. This approach achieves optimal time complexity.

The algorithm's core is a greedy strategy after sorting, which is a standard pattern for interval problems. By maintaining a single `current` interval and updating its end when overlaps occur, the solution avoids unnecessary comparisons. The final output is a clean list of non-overlapping intervals, essential for calendar scheduling or resource allocation tasks.

For developers preparing for technical interviews, mastering this problem demonstrates a grasp of sorting and pointer manipulation. The provided Java code is concise, but the underlying logic applies across languages. Understanding this pattern helps tackle more complex variations, like inserting new intervals or merging k sorted lists, which are common in system design.