#include <iostream>
#include <fstream>

using namespace std;

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

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

int main() {
    int a, n;
    fin >> a >> n;
    int d = 0, x = 0, y = 0;
    Euclid(a, n, d, x, y);
    while (x < 0) {
        x += n;
    }
    fout << x % n;
    return 0;
}