import java.util.Scanner;

public class Main {
	
	public static void main(String[] args) {
	Scanner s = new Scanner(System.in);
	String[] str = s.nextLine().split(":");
	s.close();
	int hour = Integer.parseInt(str[0]);
	int min =Integer.parseInt(str[1]);
	int minAns = (min+5)%60;
	int hourAns = ((min+5)/60+hour)%24;
	System.out.println(String.format("%02d", hourAns)+":"+String.format("%02d", minAns));
	
	}

}