#include <cstdio>

using namespace std;
int a,b,c,d,n,x,y;
void euclid ( int a, int b, int &x,int &y)
{
    if(b==0)
    {
        x=1; y=0;
        return;
    }

  euclid(b,a%b,x,y);
  int aux=x;
  x=y;
  y=aux-(a/b)*y;
}
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\n",x);
    return 0;
}