#include <fstream>
using namespace std;
ifstream f("inversmodular.in");
ofstream g("inversmodular.out");
int n, a, x, y, aux;

void cmmdc(int a, int b, int &x, int &y){
    if(b==0)
    {
        x=1;
        y=0;
    }
    else
    {
        int x0, y0, d;
        cmmdc(b, a%b, x0, y0);
        x=y0;
        y=x0-y0*(a/b);
    }
}

int main(){
    f>>a>>n;
    cmmdc(n, a, x, y);
    if(y<0)
    {
        aux=y/n-1;
        aux=-aux;
        y=(y+n*aux)%n;
    }
    g<<y<<"\n";
    return 0;
}