#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 a, b;
    cin >> a >> b;

    cin.ignore(4);
    double x;
    cin >> x;
    x *= 60;
    x += (x >= 0.0 ? +0.5 : -0.5);
    int c = (int)x;

    int t = a * 60 + b + (c - 9 * 60);
    t %= 24 * 60;
    t += 24 * 60;
    t %= 24 * 60;
    int h = t / 60;
    int m = t % 60;

    cout << setfill('0');
    cout << setw(2) << h << ':' << setw(2) << m << endl;

    return 0;
}