import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No0525_2 {
	public static void main(String[] args) {
		try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
			String[] input = br.readLine().split(":");
			int hour = Integer.parseInt(input[0]);
			int minute = Integer.parseInt(input[1]);

			minute += 5;
			hour = (minute > 59)? hour +1 : hour;

			System.out.println(String.format("%02d:%02d", hour % 24, minute % 60));
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}