#include <fstream>

using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int t, a, b, c, d, x, y, n;
int euclid(int a, int b, int& x, int &y);
void citire();
int main()
{
    citire();
    return 0;
}
int euclid(int a, int b, int& x, int &y)
{
    int x1, y1;
    if (b==0) {x=1; y=0; return a;}
    int d=euclid(b, a%b, x1, y1);
    x=y1;
    y=x1-y1*(a/b);
    return d;
}
void citire()
{
    fin>>a>>n;
    d=euclid(a,n,x,y);
    while(x<0) x+=n;
    fout<<x;
}