#include <fstream>

using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a,b,x,y,d,x0,y0,n,ca,c,i,x1,y1;
int cmmdc(int a,int b,int &x,int &y)
{
    if(b==0)
    {
        x=1;
        y=0;
        return a;
    }
    else
    {
        int x0=0,y0=0,d;
        d=cmmdc(b,a%b,x0,y0);
        x=y0;
        y=x0-(a/b)*y0;
        return d;
    }
}
int main()
{
    fin>>a>>n;
    c=1;
    ca=cmmdc(a,n,x,y);
    while(x<0)
        x+=n;
        fout<<x;
    return 0;
}