#include <cstdio>

using namespace std;

int euclidExt(int a, int b, int& x, int& y)
{
    if(!b)
    {
        x = 1;
        y = 0;
        return a;
    }
    int x0, y0;
    euclidExt(b, a % b, x0, y0);
    x = y0;
    y = x0 - (a / b) * y0;
}

int main()
{
    freopen("inversmodular.in", "r", stdin);
    freopen("inversmodular.out", "w", stdout);
    int a, n, x, y;
    scanf("%d%d", &a, &n);
    int d = euclidExt(a, n, x, y);
    while(x < 0) x += n;
    printf("%d", x);
    return 0;
}