#include <fstream>

using namespace std;
ifstream cin("inversmodular.in");
ofstream cout("inversmodular.out");
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()
{
    int a, n;
    cin>>a>>n;
    int x, y;
    euclid(a,n,x,y);
    while (x<0)
        x+=n;
    while (x>n)
        x-=n;
    cout<<x;
    return 0;
}