#include<stdio.h>
int main()
{
	int s, v;
	scanf("%d%d", &s, &v);
	int t;
	if (s % v == 0)
		t = s / v + 10;
	else
		t = s / v + 11;
	int h;
	if (t / 60 > 0)
		{
            h = t / 60;
		    t -= h * 60;
        }
	else if (t / 60 == 0)
            h = 0;
    printf("%02d:%02d",7-h,60-t);
	return 0;
}