import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String T = sc.next();
    String[] s = T.split(":");
    String hh = s[0];
    String mm = s[1];
    int ansh = Integer.parseInt(hh);
    int ansm = Integer.parseInt(mm) + 5;
    if(ansm >= 60) {
      ansh++;
      ansm -= 60;
    }
    if(ansh >= 24) ansh -= 24;
    String anshh = String.valueOf(ansh);
    String ansmm = String.valueOf(ansm);
    if(ansh < 10) anshh = "0" + anshh; 
    if(ansm < 10) ansmm = "0" + ansmm; 
    System.out.println(anshh + ":" + ansmm);
  }
}