leetcode: 630. Course Schedule III

problem

• https://leetcode.com/problems/course-schedule-iii/

greedy with heap

class Solution {
    fun scheduleCourse(courses: Array<IntArray>): Int {
        courses.sortBy { it[1] } // ascending order by last day
        val queue = PriorityQueue<Int>(compareBy { -it }) // descending order by duration
        var curr = 0
        courses.forEach { course ->
            curr += course[0] // accumulate duration
            queue.add(course[0])
            if (curr > course[1]) { // exceed last day
                curr -= queue.poll() // remove biggest duration course
            }            
        }        
        return queue.size
    }
}