#include <iostream>
#include <fstream>
#include <stdlib.h>
std::ifstream in("inversmodular.in");
std::ofstream out("inversmodular.out");

using namespace std;

long long  euclid(long long a,long long b, long long &x, long long &y)
{
    if(b==0)
    {
        x=1;
        y=0;
        return a;
    }
    long long d,x0,y0;
    d=euclid(b,a%b,x0,y0);

    x=y0;
    y=x0-(a/b)*y0;
    return d;
}
long long n,p,a,b,x,y,d;
int main()
{
    in>>n>>p;
    d=euclid(n,p,x,y);
    while(x<0)
        x+=p;
    out<<x;
    return 0;
}