#include <iostream>
#include <fstream>

using namespace std;

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

void gcd(int a, int b, int &x, int &y) {
    if(b == 0) {
        x = 1;
        y = 0;
        return;
    }
    int x0,y0;
    gcd(b, a%b, x0, y0);
    x = y0;
    y = x0 - (a/b)*y0;
}

int main() {

    int a,n,inv,y;
    in >> a >> n;
    gcd(a, n, inv, y);
    inv = (inv+n)%n;
    out << inv;

    return 0;
}