#include <fstream>

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