#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");

int A, N;

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

int main()
{
    long long inv=0, ins;
    fin>>A>>N;
    euler(inv,ins,A,N);
    if(inv<=0)
        inv=N+inv%N;
    fout<<inv;
    return 0;
}