import java.util.*;

public class Main {
	static Scanner sc = new Scanner(System.in);
	public static void main(String[] args) {
		String[] s = sc.next().split(":");
		int[] ar = {Integer.parseInt(s[0]),Integer.parseInt(s[1])};
		int minute = ar[0]*60 + ar[1] + 5;
		int h = (minute/60)%24;
		int m = minute%60;
		String ans = "";
		if (h < 10) {ans += "0";}
		ans += h + ":";
		if (m < 10) {ans += "0";}
		ans += m;
		System.out.println(ans);
	}
}