#include<bits/stdc++.h>
using namespace std;
int main()
{
	int s,v,t1,t2,t3,t4,t5,t6,t7;
	cin>>s>>v;
	t1=s/v+10;
	t5=t1/60;
	if(t1>=60)
	  {
		t1=t1-t5*60;
		t2=8-t5;
		if(t2<=0)
		  {
		  	t6=abs(t2);
			t2=24-t6;
		  }
	  }
	t3=8-t2;
	if(t3<=0)
	  {
	  	t7=abs(t3);
		t3=24-t7;
	  }
	t4=60-t1;
	if(t3<=9&&t4<=9) cout<<"0"<<t3<<":"<<"0"<<t4;
	if(t4<=9) cout<<t3<<":"<<"0"<<t4;
	if(t3<=9) cout<<"0"<<t3<<":"<<t4;
	if(t3>=10&&t4>=10) cout<<t3<<":"<<t4;
	return 0;
}
//这是上学迟到我的答案，一直报错