#include<fstream>

using namespace std;

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

int A, N;

void euclid3(int a, int b, int &x, int &y)
{
    if(b == 0)
    {
        x = 1;
        y = 0;
        return;
    }

    int q = a/b;
    int x1, y1;
    euclid3(b, a%b, x1, y1);
    x = y1;
    y = x1 - q * y1;
}

int main()
{
    f >> A >> N;
    int x,y;
    euclid3(A, N, x, y);
    while(x < 0)

        x += N;
    g << x << '\n';
    return 0;
}