package com.company;

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int hour = Integer.parseInt(scan.nextLine());
        int minutes = Integer.parseInt(scan.nextLine());

        if (minutes < 60) {
            minutes = minutes + 15;
            int mins = minutes % 60;

            if (minutes >= 60) {
                hour = hour + 1;
            }
            if (hour > 23) {
                hour = 0;
            }

            if (mins <= 9) {
                System.out.printf("%d:0%d", hour, mins);
            } else {
                System.out.printf("%d:%d", hour, mins);
            }
        }
    }
}