#include <fstream>
#define ll long long
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int A,N;
ll inv,ins;
void invers (int a, int b, ll &x, ll &y)
{
    if(!b)
        x=1,y=0;
    else
    {
        invers(b,a%b,x,y);
        ll aux=x;
        x=y;
        y=aux-y*(a/b);
    }
}
int main()
{
    fin>>A>>N;
    invers(A,N,inv,ins);
    if(inv<=0)
        inv=inv%N+N;
    fout<<inv;
    return 0;
}