#include<iostream>
#include<algorithm>
#include<string>
#include<map>
#include<cmath>
#include<vector>
#include<queue>
#include<set>
#include<stdio.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i,n) REP(i,0,n)
#define INF 1e9

int main()
{
	int a, b, ans = 0;
	cin >> a >> b;
	if (a < b) {
		ans += b - a - 1;
		ans += a - 1;
	} else {
		ans += 2000000000 - a;
		ans += a - b - 1;
	}
	cout << ans << endl;
	return 0;
}