Find Right Interval

arraybinary searchsorting

Problem Statement

You are given an array of intervals , where intervals[i] = [start _i , end _i ] and each start _i is unique .

The right interval for an interval i is an interval j such that start _j >= end _i and start _j is minimized . Note that i may equal j .

Return an array of right interval indices for each interval i . If no right interval exists for interval i , then put -1 at index i .

Examples

Example 1

Input: intervals = [[1,2]]
Output: [-1]
There is only one interval in the collection, so it outputs -1.

Example 2

Input: intervals = [[3,4],[2,3],[1,2]]
Output: [-1,0,1]
There is no right interval for [3,4].
The right interval for [2,3] is [3,4] since start _0 = 3 is the smallest start that is >= end _1 = 3.
The right interval for [1,2] is [2,3] since start _1 = 2 is the smallest start that is >= end _2 = 2.

Example 3

Input: intervals = [[1,4],[2,3],[3,4]]
Output: [-1,2,-1]
There is no right interval for [1,4] and [3,4].
The right interval for [2,3] is [3,4] since start _2 = 3 is the smallest start that is >= end _1 = 3.

Constraints

1 <= intervals.length <= 2 * 10 ^4

intervals[i].length == 2

-10 ^6 <= start _i <= end _i <= 10 ^6

The start point of each interval is unique .

🤔

Medium

Difficulty

Topic Info

ModuleDSA

CategoryArray

Sub-topicBinary Search