#include <algorithm>
#include <array>
#include <cmath>
#include <cstdio>
#include <iostream>
#include <numeric>
#include <optional>
#include <queue>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

int main() {
    int32_t a, b;
    cin >> a >> b;
    int32_t ans;
    if (a < b)
        ans = (a - 1) + (b - a - 1);
    else
        ans = (int32_t(2e9) - a) + (a - b - 1);
    cout << ans << endl;
    return 0;
}