#include <fstream>
using namespace std;

long long A, N;

void euclid(long long a, long long b, long long &d, long long &x, long long &y) {
    if(b == 0) {
        a = d;
        x = 1;
        y = 0;
    }
    else {
        long long x0 = 0, y0 = 0;

        euclid(b, a % b, d, x0, y0);
        x = y0;
        y = x0 - (a / b) * y0;
    }
}

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

    f >> A >> N;

    long long d = 1, x = 0, y = 0;

    euclid(A, N, d, x, y);
    while(x < 0)
        x += N;

    g << x << "\n";

    f.close();
    g.close();

    return 0;
}