#include <cstdio>

using namespace std;
int a,n,x,y,d;
void euclid (int a, int b, int &x, int &y)
{
    int x0,y0;
    if (b==0)
    {
        x=1;
        y=0;
        return;
    }
    euclid(b,a%b,x0,y0);
    x=y0;
    y=x0-(a/b)*y0;
    return;
}
int main()
{
    freopen ("inversmodular.in","r",stdin);
    freopen ("inversmodular.out","w",stdout);
    scanf ("%d %d", &a, &n);
    euclid(a,n,x,y);
    x%=n;
    if (x<0)
        x+=n;
    printf ("%d", x);
    return 0;
}