#include <iostream>
using namespace std;

int
main()
{
  int a, b;
  int ret;
  cin >> a;
  cin >> b;

  if (a > b) {
    // c > b && c != a
    ret = 2000000000 - b - 1;
  } else {
    // b > c && c != a
    ret = b - 1 - 1;
  }

  cout << ret << endl;
}