class Clock {

    public static void main(String[] args) {
	Clock one = new Clock("2350"); 
	for (int i = 0; i < 20; i++) {
	    one.tick(); 
	    System.out.println(one.report()); 
        }
    }

    int hours, minutes; 
    Clock(String time) {
	hours = Integer.parseInt(time.substring(0, 2)); 
	minutes = Integer.parseInt(time.substring(2)); 
    }
    void tick() {
        minutes += 1; 
        if (minutes == 60) { 
	    minutes = 0; 
	    hours += 1; 
	}
        if (hours == 24) {
	    hours = 0; 
	}
    }
    String report() {
        String hours = "00" + this.hours; 
	String minutes = "00" + this.minutes;
	return 
	    hours.substring(hours.length() - 2) + ":" + 
	    minutes.substring(minutes.length() - 2); 
    }
}