#include <cstdio>

using namespace std;
int euclid(int a, int b, int &x, int &y);
int main()
{
    freopen("inversmodular.in","r",stdin);
    freopen("inversmodular.out","w",stdout);
    int a, b, sol, x, y;
    scanf("%d%d",&a,&b);
    sol=euclid(a, b, x, y);
    while(x<0) x+=b;
    printf("%d",x);
}
int euclid(int a, int b, int &x, int &y)
{
    if(b==0)
    {
        x=1; y=0;
        return a;
    }
    int d, x0, y0;
    d=euclid(b, a%b, x0, y0);
    x=y0;
    y=x0-y0*a/b;
    return d;
}