#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

int main()
{
    int h, m;
    char tmp;
    cin >> h >> tmp >> m;

    int t = (h * 60 + m + 5) % (24 * 60);
    h = t / 60;
    m = t % 60;
    cout << setfill('0') << setw(2) << h << ':' << setw(2) << m << endl;

    return 0;
}