g0401_0500.s0435_non_overlapping_intervals

Class Solution

java.lang.Object

g0401_0500.s0435_non_overlapping_intervals.Solution

public class Solution
extends Object

435 - Non-overlapping Intervals.

Medium

Given an array of intervals intervals where intervals[i] = [starti, endi], return the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.

Example 1:

Input: intervals = 1,2],[2,3],[3,4],[1,3

Output: 1

Explanation: [1,3] can be removed and the rest of the intervals are non-overlapping.

Example 2:

Input: intervals = 1,2],[1,2],[1,2

Output: 2

Explanation: You need to remove two [1,2] to make the rest of the intervals non-overlapping.

Example 3:

Input: intervals = 1,2],[2,3

Output: 0

Explanation: You don’t need to remove any of the intervals since they’re already non-overlapping.

Constraints:

• 1 <= intervals.length <= 105
• intervals[i].length == 2
• -5 * 104 <= starti < endi <= 5 * 104

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int	eraseOverlapIntervals(int[][] intervals) This is sorting my starting time, the key here is that we’ll want to update end time when an erasure is needed: we use the smaller end time instead of the bigger one which is more likely to overlap with others.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

eraseOverlapIntervals

public int eraseOverlapIntervals(int[][] intervals)

This is sorting my starting time, the key here is that we’ll want to update end time when an erasure is needed: we use the smaller end time instead of the bigger one which is more likely to overlap with others.