#include<iostream>
#include<cmath>
#include<iomanip>
using namespace std;
int main(){
   int a,b;
   cin>>a>>b;
   if(a%b!=0){
   	a=a/b+1;
   }else{
   	a/=b;
   }
   int cot=(a+10);
   int f=32*60-a-10;
   int fz,xs;
   fz=f%60;
   
   xs=f/60%24;
   if(xs>10){
   	if(fz<10){
   		cout<<xs<<":"<<"0"<<fz;
   		return 0;
	   }
   	cout<<xs<<":"<<fz;
   } else{
   		if(fz<10){
   		cout<<"0"<<xs<<":"<<"0"<<fz;
   		return 0;
	   }
   	cout<<"0"<<xs<<":"<<fz;
   }
   return 0;
}