import java.util.Scanner;

public class No652 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int min = a*60 + b;
		String s = sc.next();
		double utc;
		if(s.charAt(3) == '+') {
			utc = Double.parseDouble(s.substring(4));
		}else {
			utc = Double.parseDouble(s.substring(3));
		}
		min = (int)(min + (utc - 9) * 60) % 1440;
		if(min < 0) {
			min += 1440;
		}
		System.out.printf("%02d:%02d\n",min/60,min%60);
	}
}