#include "bits/stdc++.h"

using namespace std;
using ll = long long;
using IP = pair<int, int>;


#define INF 999999999
#define atcoder(int)1e9+7
#define Endl endl

int main() {

	int a ,b;
	char  c;

	cin >> a >> c >> b;

	b += 5;
	if (b > 60) {
		b -= 60;
		a++;
	}
	if (a > 23) {
		a = 0;
	}
	if (a < 10)cout << '0' << a << c;
	else cout << a << c;

	if (b < 10) cout << '0' << b << endl;
	else cout << b << endl;

	return 0;
}