#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main()
{
  int a, b;
  cin >> a >> b;
  int ans = 1e5;
  for (int x = 1; x <= 1e5; ++x)
  {
    if (x % a == b % x)
    {
      ans = x;
      break;
    }
  }
  cout << ans << endl;
}