#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < n; ++i)
#define rep3(i, l, n) for (int i = l; i < n; ++i)
#define chmax(a, b) a = (a >= b ? a : b)
#define chmin(a, b) a = (a <= b ? a : b)
#define out(a) cout << a << endl
#define outa(a, n) rep(_, n) cout << a[_] << " "; cout << endl
#define SZ(v) (int)v.size()
#define inf (int)(1e9+7)
#define abs(x) (x >= 0 ? x : -(x))

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int a, b; char ch;
    cin >> a >> ch >> b;
    // out(a << " " << ch << " " << b);
    if (b + 5 >= 60) {
        cout << setw(2) << setfill('0') << (a + 1) % 24;
        cout << ":";
        cout << setw(2) << setfill('0') << (b + 5) % 60 << endl;
    } else {
        cout << setw(2) << setfill('0') << a;
        cout << ":";
        cout << setw(2) << setfill('0') << b + 5 << endl;
    }
    
}