#include <stdio.h>
#include <algorithm>
using namespace std;
using ll = long long;

int main() {
	int h, m, t;
	scanf("%d:%d", &h, &m);
	t = (h * 60 + m + 5) % (24 * 60);
	printf("%02d:%02d\n", t / 60, t % 60);
}