#include<algorithm>
using namespace std;

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

int main ()
{
    freopen("inversmodular.in","r",stdin);
    freopen("inversmodular.out","w",stdout);
    int a,n;
    long long inv,aux;

    scanf("%d%d",&a,&n);
    euclid(a,n,inv,aux);

    if(inv<0)
        inv=n+inv%n;

    printf("%lld",inv);
    return 0;
}