#include <bits/stdc++.h>

using namespace std;

#define int long long
#define all(v) (v).begin(), (v).end()
#define resz(v, ...) (v).clear(), (v).resize(__VA_ARGS__)
#define reps(i, m, n) for(int i = (int)(m); i < (int)(n); i++)
#define rep(i, n) reps(i, 0, n)

template<class T1, class T2> void chmin(T1 &a, T2 b){if(a>b)a=b;}
template<class T1, class T2> void chmax(T1 &a, T2 b){if(a<b)a=b;}

typedef pair<int, int> Pi;
typedef tuple<int, int, int> Ti;
typedef vector<int> vint;

const int inf = 1LL << 55;
const int mod = 1e9 + 7;

signed main()
{
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  cout << fixed << setprecision(12);

  int h, m;
  scanf("%lld:%lld", &h, &m);
  int x = (h*60+m+5)%(24*60);
  printf("%02lld:%02lld\n",x/60, x%60);

  return 0;
}