#include <iostream>
using namespace std;
int main(int argc, char* argv[])
{
	int A,B;
	cin>>A>>B;
	int ans=0;
	if (A>B){
		//must B<C;
		ans=A-B-1+2000000000-A;
	}else if (A<B){
		//must B>C
		ans=B-A-1+A-1;
	}
	cout<<ans<<endl;
	return 0;
}