import java.util.Scanner;

/**
 * Created by Radi Kamen on 4/23/2017.
 */
public class add15mins {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int hour = Integer.parseInt(scanner.nextLine());

        if (hour >= 0 && hour <= 23) { // check hour diapason 0 to 23 hours
            int mins = Integer.parseInt(scanner.nextLine());
            int add15mins = mins + 15;

            if (add15mins > 59){ // check minutes
                hour = hour + 1;
                add15mins = add15mins - 60;
            }

            if (hour >= 24) {
                hour = 00;
            }

            if (add15mins >= 0 && add15mins <= 9) {
                System.out.println(hour + ":0" + add15mins);
            } else if (add15mins >= 10 & add15mins <= 59) {
                System.out.println(hour + ":" + add15mins);
            } else {
                System.out.println("error mins");
            }
        } else {
            System.out.println("error hour");
        }
    }
}