NonOverlapClass.java

import java.util.Arrays;
import java.util.Comparator;

class Duration{
    int start;
    int finish;

    public Duration(int start, int finish){
        this.start=start;
        this.finish=finish;
    }
}

public class NonOverlapClass {
    
    public static int NonOverlapClass(Duration schedules[]){
        Arrays.sort(schedules, Comparator.comparingInt(cs -> cs.finish));

        int count=0;
        int last_finish=0;

        for (Duration schedule : schedules) {
            if (schedule.start >= last_finish) {
                count++;
                last_finish = schedule.finish;
            }
        }

        return count;

    }

    public static void main(String[] args) {
        
        Duration[] schedules = {
            new Duration(1, 2),
            new Duration(3, 4),
            new Duration(0, 6),
            new Duration(5, 7),
            new Duration(8, 9),
            new Duration(5, 9)
        };

        int maxClasses = NonOverlapClass(schedules);
        System.out.println("Maximum number of non-overlapping classes: " + maxClasses);
    }
}