import java.util.Scanner;

class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str=sc.nextLine();
		sc.close();

		int hour=Integer.parseInt(str.substring(0,2));
		int min=Integer.parseInt(str.substring(3));
		min+=5;
		if(min>=60){
			min-=60;
			hour+=1;
			if(hour>=24){
				hour-=24;
			}
		}

		String result="";
		if(hour<10){
			result+="0"+hour;
		}else{
			result+=hour;
		}
		if(min<10){
			result+=":0"+min;
		}else{
			result+=":"+min;
		}
		System.out.println(result);
	}
}