#include <iostream>
#include <iomanip>
using namespace std;
int main(void) {
	int h, m;
	char c;
	cin >> h >> c >> m;
	m += 5;
	if (m >= 60) {
		++h;
		m = m % 60;
		if (h >= 24) h = h % 24;
	}
	cout << setfill('0') << right;
	cout << setw(2) << h << ':' << setw(2) << m << endl;
	return 0;
}