#include <iostream>
#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()
{
    int x, y;
    fin>>a>>n;
    euclid_extins(a, n, x, y);

    while(x < 0)
        x += n;
    fout<<x;
    return 0;
}