import java.util.Scanner;

public class task4 {
    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 allminutes = hours*60 + minutes + 30;

        int newHours = allminutes/60;
        int newMinutes = allminutes%60;

        if (newHours > 23){
            System.out.printf("0:%d", newMinutes);
            if (newMinutes <10){
                System.out.printf("0:0%d", newMinutes);

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