#include <iostream>
#include <cstdio>

using namespace std;

long long a, n;

pair<long long, long long> euclid_extins(long long x, long long y)
{
    if(y==0)
        return {1,0};
    auto p=euclid_extins(y, x%y);
    return {p.second, p.first-(x/y)*p.second};
}

int main()
{
    freopen("inversmodular.in", "r", stdin);
    freopen("inversmodular.out", "w", stdout);

    scanf("%lld %lld", &a, &n);
    pair<long long, long long> r=euclid_extins(a, n);
    while(r.first<0)
        r.first+=n;
    printf("%lld", r.first);
    return 0;
}