#include <fstream>
using namespace std;

ifstream is("inversmodular.in");
ofstream os("inversmodular.out");

int Modul( int N, int A );

int main()
{
    int N, A;
    is >> N >> A;
    os << Modul ( N, A );
    is.close();
    os.close();
    return 0;
}

int Modul( int N, int A )
{
    int x = 0, y;
    for ( y = 0; x == 0; y++ )
        if ( ( N * y + 1 ) % A == 0 )
            x = ( N * y + 1 ) / A;
    return x;
}