import java.util.Scanner;

public class TimePlus15Min {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int hours = Integer.parseInt(scanner.nextLine());
        int minutes = Integer.parseInt(scanner.nextLine());

        int time = minutes + 15;

        if (time > 59) {
            hours = hours + 1;
            time = time - 60;
        }

        if (hours > 23) {
            hours = hours - 24;
        }

        if (time < 10) {
            System.out.printf("%d:0%d", hours, time);
        }
        else {
            System.out.printf("%d:%d", hours, time);
        }

    }
}