public class Surtur {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		long x = System.currentTimeMillis()/1000;
		long D = x/3600/24;
		long H = x/3600-D*24;
		long M = x/60-x/3600*60;
		long S = x-(D*3600*24+H*3600+M*60);
		System.out.println(D+":"+H+":"+M+":"+S);
	}
}