#include <fstream>
using namespace std;
ifstream cin("inversmodular.in");
ofstream cout("inversmodular.out");
int A,N;
long long inv=0,ins;
void gcd(long long &x, long long &y, int a, int b)
{
    if(!b)
    {
        x=1;
        y=0;
    }
    else
    {
        gcd(x,y,b,a%b);
        long long aux=x;
        x=y;
        y=aux-y*(a/b);
    }
}
int main()
{
    cin>>A>>N;
    gcd(inv,ins,A,N);
    if(inv<=0)
        inv=N+inv%N;
    cout<<inv;
    return 0;
}