#include <bits/stdc++.h>

using namespace std;

int main(int argc, char **argv) {
	int h, m;
	scanf("%d:%d", &h, &m);

	struct tm t;
	t.tm_year = 100;
	t.tm_mon = 1;
	t.tm_mday = 1;
	t.tm_hour = h;
	t.tm_min = m + 5;
	t.tm_sec = 0;

	time_t ret = mktime(&t);

	printf("%02d:%02d\n", t.tm_hour, t.tm_min);

	return 0;
}