#include <fstream>

using namespace std;

ifstream f("invmod.in");
ofstream g("invmod.out");

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

int main() {
    int x, y,a,mod;
    f >> a >> mod;
    x = y = 0;
    euclid(a,mod,x,y);
    if (x < 0)
        x += mod;
    g << x;
    return 0;
}