#include <fstream>
using namespace std;
ifstream in("inversmodular.in");
ofstream out("inversmodular.out");

void gcd(long long int &x,long long int &y, int a, int b)
{
    if(!b)
    {
        x=1;
        y=0;
    }
    else
    {
        gcd(x,y,b,a%b);
        long long aux=x;
        x=y;
        y=aux-y*(a/b);
    }
}

int main()
{
    int A,N;
    long long inv, ins;
    in>>A>>N;
    gcd(inv,ins,A,N);
    if(inv<=0) inv+=N;
    out<<inv;
    return 0;
}