import java.util.Arrays;
import java.util.Scanner;

public class Solution{
	static Scanner s=new Scanner(System.in);
	public static void main(String[]__){
		int[] in=Arrays.stream(s.next().split(":")).mapToInt(Integer::parseInt).toArray();
		
		if(in[1]>54) {
			in[0]++;
			in[0]%=24;
			in[1]-=60;
		}
		in[1]+=5;
		System.out.printf("%02d:%02d\n",in[0],in[1]);
	}
}