#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int A, N, X;
int euclid(int a, int b, int *x, int *y)
{
    if(b)
    {
        int x0, y0;
        euclid(b, a % b, &x0, &y0);
        *x = y0;
        *y = x0 - y0 * (a / b);
    }
    else
    {
        *x = 1;
        *y = 0;
    }
}
int main()
{
    int u, v;
    fin>>A>>N;
    euclid(A, N, &u, &v);
    while(u < 0)
    {
        u += N;
    }
    fout<<u;
    return 0;
}