#include<stdio.h>
#include<math.h>
int main()
{
	//一天3600分钟； 
	int m,n;
	int h;
	scanf("%d%d",&m,&n);
	double a=m*1.0/n;
	if(a!=0)
	{
		h=ceil(a);
	}
	else
	{
		h=m/n;
	}
	 int j=1430-h;
	 int k=8+j/60;
	 int l=j%60;
	 if(k>=24)
	 k-=24;
	 printf("%02d:%02d",k,l);
	
	
	
	
}