#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <stack>
#include <algorithm>
#include <string>
#include <map>
#include <iterator>
#include <set>
#include <queue>
#include <bitset>
#include <cassert>

using namespace std;


int asInt(string ss) {
    assert(ss.size() == 2);
    if (ss[0] == 0) {
        return ss[1] - '0';
    } else {
        return (ss[0] - '0') * 10 + (ss[1] - '0');
    }
}

string asStr(int i) {
    if (i < 10) {
        return "0" + to_string(i);
    } else {
        return to_string(i);
    }
}

int main() {


    string T;
    cin >> T;
    int hour = asInt(T.substr(0, 2));
    int minute = asInt(T.substr(3, 2));

    minute += 5;
    int carry = 0;
    if (minute >= 60) {
        carry = 1;
        minute = minute % 60;
    }

    hour += carry;
    hour = hour % 24;

    cout << (asStr(hour) + ":" + asStr(minute)) << endl;

    return 0;
}