#include <bits/stdc++.h>

using namespace std;

using ll = long long;

void gcd(ll &x, ll &y, int a, int b) {
     if (!b)
         x = 1, y = 0;
     else {
         gcd(x, y, b, a % b);
         ll aux = x;
         x = y;
         y = aux - y * (a / b);
     }
}

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

    ll a, n, inv = 0, ins;

    in >> a >> n;

    gcd(inv, ins, a, n);

    if (inv <= 0)
       inv = n + inv % n;

    out << inv;

    return 0;
}