//#define LOCAL

#include <fstream>
#include <iostream>
#include <cmath>
#include <algorithm>
#include <vector>
#include <map>
#include <queue>
#include <cstring>
#include <climits>
#include <set>

//#define int long long
//typedef long long ll;
using ll = long long;
using R = double;

//#define rep(i,n) for(int i=0; i<(n); i++)
#define FOR(i,bg,ed) for(ll i=(bg);i<(ed);i++)
#define REP(i,n) FOR(i,0,n)

#define MOD 1000000007

using namespace std;

typedef vector<int> V;
typedef vector<V> VV;

signed main()
{
#ifdef LOCAL
    ifstream in("input.txt");
    cin.rdbuf(in.rdbuf());
#endif

    int hh, mm;
    char c;

    cin >> hh >> c >> mm;
    mm += 5;
    if (mm >= 60) {
        mm %= 60;
        hh++;
        if (hh >= 24) {
            hh %= 24;
        }
    }

    printf("%02d:%02d\n", hh, mm);

    return 0;
}