Merge Intervals in Java: Explanation & Practice

Problem summary

Given a list of intervals, merge all overlapping intervals.

Starter code

import java.util.*;

public class Main {
    public static void main(String[] args) {
        int[][] intervals = {{1,3}, {2,6}, {8,10}, {15,18}};
        
        // Merge overlapping intervals
        // Print: [1,6] [8,10] [15,18]
    }
}

Expected output and test cases

• [1,3] and [2,6] merge

  [1,6] [8,10] [15,18]

• All intervals overlap

  [1,5]

Hints

1. Sort by start time
2. Compare end of current with start of next
3. Extend current interval if overlapping

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