#include <fstream>

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