#include <iostream>
#include <fstream>
using namespace std;
ifstream f("spion1.in");
ofstream g("spion1.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 A, N; // prime intre ele, 1 <= A < N
int main()
{
    f>>A>>N;
    int X , Y;
    euclid(A, N , X ,Y);
    while(X < 0)
        X += N;
    g << X;
    return 0;
}