#include <bits/stdc++.h>
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a, n;

void gcd(long long &x, long long &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()
{
    long long inv = 0, ins;

    fin >> a >> n;
    gcd(inv, ins, a, n);

    if(inv <= 0)
        inv = inv % n + n;

    fout << inv;

    return 0;
}