#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");

void inv(long long a,long long b,long long &x,long long &y)
{
    if (b == 0)
    {
        x = 1;
        y = 0;
        return;
    }
    long long i,j;
    inv(b,a%b,i,j);
    x = j;
    y = i - (a/b)*j;
}

int main()
{
    long long A,N,x,y;
    fin>>A>>N;
    inv(A,N,x,y);
    if (x<=0)
        x = N + x;
    fout<<x;

    return 0;
}