#include <cstdio>


int main() {
	int h, m;
	scanf("%02d:%02d", &h, &m);

	m = h * 60 + m + 5;
	if (m > 60 * 24) m -= 60 * 24;

	printf("%02d:%02d", m / 60, m % 60);

	return 0;
}