#include <bits/stdc++.h>

using namespace std;

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

void euclid(int a , int b ,int & x ,int & y)
{
    if(b == 0)
    {
        x = 1;
        y = 1;
    }
    else
    {
        int x1, y1;
        euclid(b, a % b, x1, y1);
        x = y1;
        y = x1 - (a / b) * y1;
    }
}

int main()
{
    int A, N;
    fin >> A >> N;

    int X, Y;
    euclid(A, N , X ,Y);

    while(X < 0) X += N;

    fout << X;

    return 0;
}