#include <fstream>

using namespace std;

ifstream f("inversmodular.in");
ofstream g("inversmodular.out");

int a, b, x, y;

int euclid(int a, int b, int &x, int &y)
{
    if (b == 0)
    {
        x = 1;
        y = 0;
        return a;
    }
    else
    {
        int xx, yy;
        euclid(b, a % b, xx, yy);
        x = yy;
        y = xx - (a / b) * yy;
    }
}

int main()
{
    f >> a >> b;

    euclid(a, b, x, y);

    while (x < 0)
        x += b;

    g << x << '\n';
    return 0;
}