LeetCode in Kotlin
1288. Remove Covered Intervals
Medium
Given an array intervals where intervals[i] = [li, ri] represent the interval [li, ri), remove all intervals that are covered by another interval in the list.
The interval [a, b) is covered by the interval [c, d) if and only if c <= a and b <= d.
Return the number of remaining intervals.
Example 1:
Input: intervals = [[1,4],[3,6],[2,8]]
Output: 2
Explanation: Interval [3,6] is covered by [2,8], therefore it is removed.
Example 2:
Input: intervals = [[1,4],[2,3]]
Output: 1
Constraints:
1 <= intervals.length <= 1000intervals[i].length == 20 <= li < ri <= 105- All the given intervals are unique.
Solution
import java.util.PriorityQueue
import java.util.Queue
class Solution {
fun removeCoveredIntervals(intervals: Array<IntArray>): Int {
val q: Queue<IntArray> = PriorityQueue { a: IntArray, b: IntArray
->
if (a[0] == b[0]) b[1] - a[1] else a[0] - b[0]
}
for (interval in intervals) {
q.offer(interval)
}
var prev = q.poll()
var count = 0
while (q.isNotEmpty()) {
val curr = q.poll()
if (curr[0] >= prev[0] && curr[1] <= prev[1]) {
count++
} else {
prev = curr
}
}
return intervals.size - count
}
}