#include <iostream>
#include <fstream>

using namespace std;

void euclid(int a, int b, int &x, int &y)
{
    if(b==0)
    {
        x=1;
        y=0;
    }
    else
    {
        int x0, y0;
        euclid(b, a%b, x0, y0);
        x=y0;
        y=x0-(a/b)*y0;
    }
}
int main()
{
    ifstream in("inversmodular.in");
    ofstream out("inversmodular.out");

    int a, n, x, y, d;
    in>>a>>n;
    euclid(a, n, x, y);
    if(x<0)
        out<<x+n;
    else out<<x;
    return 0;
}