#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using llu = long long unsigned;

vector<ll> dx = { 0, 0, -1, 1};
vector<ll> dy = {-1, 1,  0, 0};

#define MOD 1000000007
int main() {
    string T;
    cin >> T;
    int hour, min;
    string sh = T.substr(0, 2);
    string sm = T.substr(3, 2);
    hour = stoi(sh);
    min = stoi(sm);
    min += 5;
    if (min >= 60) { min%=60; hour++; }
    if (hour >= 24) { hour%=24; }
    printf("%02d:%02d\n", hour, min);
    return 0;
}