#include <fstream>
using namespace std;
ifstream  fin("inversmodular.in");
ofstream fout("inversmodular.out");
int A,N;

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

int main()
{
    fin>>A>>N;

    int x,y;
    euclid_extins(A,N,x,y);

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

    fout<< x << "\n";

    return 0;
}