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Merge Intervals

Understand how to identify and merge overlapping intervals within an array, returning consolidated non-overlapping intervals. This lesson helps develop skills to handle common interval problems by working through examples and implementing solutions step by step.

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Statement

We are given an array of closed intervalsclosedintervals called intervals, where each interval has a start time and an end time and is represented as intervals[i] = [starti, endi]. Your task is to merge all the overlapping intervalsOverlapping intervals are two or more intervals with at least one common point in time. and return an array of the resulting non-overlapping intervals that cover all the intervals in the input.

Constraints:

  • 1≤1 \leq intervals.length ≤103\leq10^3

  • intervals[i].length ==2== 2

  • 0≤0\leq starti ≤\leq endi ≤104\leq10^4

Examples

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Understand the problem

Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

Merge Intervals

1.

Given the intervals below, what is the correct output after merging the overlapping intervals?

[ [1, 6], [2, 4] ]

A.

[ [2, 4] ]

B.

[ [1, 6] ]

C.

[ [1, 6], [2, 4] ]

D.

[ [2, 4], [1, 6] ]

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Figure it out

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Sequence - Vertical
Drag and drop the cards to rearrange them in the correct sequence.
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Try it yourself

Implement your solution in the following coding playground.

Java
usercode > Solution.java
import java.util.*;
class Solution {
    public static int[][] mergeIntervals(int[][] intervals) {
        // Replace this placeholder return statement with your code
        return new int[][]{};
    }
}
Merge Intervals