#include <fstream>
#define ull unsigned long long
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a, n;
void euclidextins(int a, int b, int &x, int &y)
{
    if(b == 0)
    {
        x = 1, y = 1;
    }
    else
    {
        int x0, y0;
        euclidextins(b, a % b, x0, y0);
        x = y0;
        y = x0 - (a / b) * y0;
    }
}
int main()
{
    fin >> a >> n;
    int x, y;
    euclidextins(a, n, x, y);
    while(x < 0) x += n;
    fout << x;
    return 0;
}