#include <fstream>
#define ll long long
using namespace std;
ifstream f("inversmodular.in");
ofstream g("inversmodular.out");
ll a,n,inv,p;
void gcd(ll &x,ll &y,ll a,ll b)
{
if(b==0)
{
x=1;
y=0;
}
else {
    gcd(x,y,b,a%b);
    ll aux=x;
    x=y;
    y=aux-y*(a/b);
}
}
int main()
{
    f>>a>>n;
    gcd(inv,p,a,n);
    if(inv<=0)inv=n+inv%n;
    g<<inv;
    return 0;
}