hours:minutes + 15 if - else

import java.util.Scanner;

/**
 * Created by Nasko on 16.7.2017 г..
 */
public class TimePlus15 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

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

        minutes+=15;

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

        if (hours>23) {
            if (minutes < 10) {
                System.out.printf("0:0%d", minutes);
            } else
                System.out.printf("0:%d", minutes);
        } else {
            if (minutes < 10) {
                System.out.printf("%d:0%d",hours, minutes);
            } else {
                System.out.printf("%d:%d", hours, minutes);
            }
        }


    }
}