#include<bits/stdc++.h>
using namespace std;

int main(){
	int x,y;
	cin>>x>>y;
	int d=ceil((double)(y-x)/2);
	if(d<=12000)cout<<5<<endl;
	else if(d<=10000)cout<<6<<endl;
	else if(d<=24000)cout<<8<<endl;
	else if(d<=36000)cout<<11<<endl;
	else {int x=ceil((double)d/48000);cout<<13*x<<endl;}

	
return 0;
}