#include <fstream>
using namespace std;
void euclid_extins(int *x, int *y, int a, int b)
{
    if(b==0)
    {
         *x=1;
         *y=0;
    }
    else
    {
        int x0,y0,c=a/b;
        euclid_extins(&x0,&y0,b,a%b);
        *x=y0;
        *y=x0-c*y0;
    }
}
int main()
{
    ifstream fin("inversmodular.in");
    ofstream fout("inversmodular.out");
    int a,n;
    fin>>a>>n;
    int x,y;
    euclid_extins(&x,&y,a,n);
    while(x<0) x+=n;
    fout<<x<<'\n';
}