#include <bits/stdc++.h>
#define REP(i, a, n) for(ll i = ((ll) a); i < ((ll) n); i++)
using namespace std;
typedef long long ll;

int main(void) {
    string hour,min;
    getline(cin, hour, ':');
    getline(cin, min, '\n');
    int h = stoi(hour);
    int m = stoi(min) + 5;
    if (m > 60) { m -= 60; h++;}
    if (h > 23) h = 0;

    if (h < 10) cout << 0;
    cout << h << ':';
    if (m < 10) cout << 0;
    cout << m << endl;
    return 0;
}