#include <iostream>
#include <fstream>

using namespace std;

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

int euclid (int a, int b, int &x, int &y)
{
    if(b==0)
    {
        x=1;
        y=0;
    }

    else
    {
        int x1, y1;

        euclid(b, a%b, x1, y1);
        x=y1;
        y=x1-a/b*y1;
    }
}


int main()
{
    int a, n, x, y;

    fin>>a>>n;

    euclid (a, n, x, y);

    while(x>0)
    {
        x=x-n;
    }

    while(x<0)
    {
        x=x+n;
    }

    fout<<x;
}