#include <iostream>
#include <vector>
#include <string>
#include <iomanip>

#define REP(i, a, b) for (int i = int(a); i < int(b); i++)
#define dump(s) cerr << __LINE__ << "\t:" << #s << " = " << (s) << endl
    
using namespace std;

int main () {
    string s;
    int t, m;
    char c;
    cin >> t >> c >> m;
    int tm = (t * 60 + m + 5) % 1440;
    cout << setw(2) << setfill('0') << tm / 60 << ':' << setw(2) << setfill('0') << tm % 60 << endl;
    
    return 0; 
}