#include <bits/stdc++.h>
using namespace std;

int main() {
  int h, m;
  scanf("%d:%d", &h, &m);
  struct tm t = {};
  t.tm_hour = h, t.tm_min  = m + 5;
  mktime(&t);
  printf("%02d:%02d", t.tm_hour, t.tm_min);
}