import java.util.Scanner;

public class task4_2 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int hours = Integer.parseInt(scanner.nextLine());
        int minutes = Integer.parseInt(scanner.nextLine());

        minutes = minutes +30;

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


        }if (hours >23){
            hours = 0;

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


        }else System.out.printf("%d:%d", hours,minutes);



    }
}