import java.util.Scanner;

public class Main {
	static Scanner in = new Scanner(System.in);
	public static void main(String[] args){
		String[] ss = in.nextLine().split(":");
		int a = Integer.parseInt(ss[1]) + 5;
		int b = Integer.parseInt(ss[0]);
		if(a >= 60){
			a %= 60;
			b++;
		}
		if(b >= 24){
			b %= 24;
		}
		System.out.printf("%02d:%02d", b, a);
	}
}