#include <iostream>
using namespace std;
 
int main() {
  int arr[1000 * 1000], n, m, result = 0;
  cin >> n >> m;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++)
      arr[i * m + j] = i * m + j;
  for (int j = 0; j < m; j++) 
    for (int i = 0; i < n; i++) 
      if (arr[i * m + j] == j * n + i) result++;
  cout << result << "\n";
}