#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, m;
  cin >> n >> m;
  if (n % 2 != 0) {
    if (n == 1 && m == 1)
      cout << 1;
    else if (m == (n / 2) + 1)
      cout << m - 1;
    else if (m < (n / 2) + 1)
      cout << m + 1;
    else
      cout << m - 1;
  } else {
    if (m == (n / 2))
      cout << m + 1;
    else if (m < (n / 2))
      cout << m + 1;
    else
      cout << m - 1;
  }
}
