MaximumPerformanceofaTeam.java

class Solution {
    // TC : O(nlogn)
    // SC : O(n)

    private class Engineer{

        private int speed;
        private  int efficiency;

        public Engineer(int speed, int efficiency){

            this.speed = speed;
            this.efficiency = efficiency;
        }
    }

    public int maxPerformance(int n, int[] speed, int[] efficiency, int k) {

        List<Engineer> engineers = new ArrayList<>();

        for(int i = 0; i < n; i++) {
            engineers.add(new Engineer(speed[i], efficiency[i]));
        }

        //now sort the engineers list by their efficiency descending

       engineers.sort((a, b) -> b.efficiency - a.efficiency);

        //will keep slowest members at the top, fastest ones stay in the team longest
        PriorityQueue<Engineer> currentTeam = new PriorityQueue<>((a, b) -> a.speed - b.speed);


        long teamSpeed = 0;
        long maxPerformance = 0;

        for(Engineer newHire : engineers){

            if(currentTeam.size() == k){

                //we must evict the slowest engineer from out current team

                Engineer slowGuy = currentTeam.poll();

                //now we must remove the slow guys speed from our total speed
                teamSpeed -= slowGuy.speed;
            }

            //hire the new guy to the team
            currentTeam.add(newHire);

            //so pickup the new engineers speed and add it to the current teams speed
            teamSpeed += newHire.speed;

            // Minimum would be new hire efficiency

            long performanceWithNewGuy = teamSpeed * (long) newHire.efficiency;

             maxPerformance = Math.max(maxPerformance, performanceWithNewGuy);
        }

       return (int) (maxPerformance % 1000000007);
    }


}