#include <fstream>

using namespace std;

ifstream cin("inversmodular.in");
ofstream cout("inversmodular.out");

void euclid_extins(int a, int b, int &x, int &y) {
    if (b == 0) {
        x = 1;
        y = 0;
        return;
    }
    euclid_extins(b, a % b, x, y);
    int aux = x;
    x = y;
    y = aux - (a / b) * y;
}

int main() {
    int a, n;
    cin >> a >> n;
    int x, y;
    euclid_extins(a, n, x, y);
    x %= n;
    if (x < 0) x += n;
    cout << x;
    return 0;
}