Miscellany

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package Time;

public class Time {

    private int hours, minutes;

    Time(int hr, int min) {
        this.hours = hr + (min / 60);
        this.minutes = min % 60;
    }

    Time(double hrmin) {
        this.hours = (int) hrmin;
        this.minutes = (int) ((hrmin % 1) * 60);
    }

    @Override
    public String toString() {
        return String.format("%d:%02d", hours, minutes);
    }
    
    public int getHours() {
        return this.hours;
    }
    public int getMinutes() {
        return this.minutes;
    }
    
    public static Time difference(Time t1, Time t2) {
        return new Time(t2.getHours() - t1.getHours(), t2.getMinutes() - t1.getMinutes());
    }

    public static void main(String[] args) {

        System.out.println(new Time(9, 30));
        System.out.println(new Time(21, 30));
        System.out.println(new Time(10, 93));
        System.out.println(new Time(9.5));
        System.out.println(new Time(21.5));
        System.out.println(new Time(0, 0));
        System.out.println(new Time(0));
        System.out.println(new Time(1, 1));
        System.out.println(Time.difference(new Time(1,10), new Time(10,10)));
        System.out.println(Time.difference(new Time(7,50), new Time(8,10)));
        System.out.println(Time.difference(new Time(12,57), new Time(2,10)));

    }
}


OUTPUT
run:
9:30
21:30
11:33
9:30
21:30
0:00
0:00
1:01
9:00
1:-40
-10:-47
BUILD SUCCESSFUL (total time: 0 seconds)