#include<stdio.h>
int main(){
	int s,v,hos,min,hos1,min1;
	scanf("%d %d",&s,&v);
	min=s/v;
	hos=0;
	if(s%v!=0){
		min++;
	}
	if(min>60){
		hos=hos+(min/60);
		hos1=7-hos;
			if(hos1<0){
			hos1=24+hos1;
		}
		min=min%60;
		min1=60-(min+10);
	
	}
	else{
		hos1=7-hos;
		min1=60-(min+10);
	}
	printf("%02d:%02d",hos1,min1);
	return 0;
}