#include<bits/stdc++.h>
using namespace std;
int main() {
	int s,v,alm,min,h,m;
	cin>>s>>v;
	if(s%v==0)min=s/v;
	else min=s/v+1;//pd
	alm=min+10;
	h=alm/60;
	m=alm%60;
	if(h>=8)
		cout<<32-h<<":"<<60-m;
	else
		cout<<0<<7-h<<":"<<60-m;
}