#include <bits/stdc++.h>
using namespace std;

long long eazymod(long long a,long long m){a %= m; if(a < 0) a += m; return a;}
pair<long long,long long> invgcd(long long a,long long b){
    //return {gcd(a,b),x} (xa≡g(mod b))
    a = eazymod(a,b);
    if(a == 0) return {b,0};
    long long x = 0,y = 1,memob = b;
    while(a){
        long long q = b/a;
        b -= a*q;
        swap(x,y); y -= q*x;
        swap(a,b);
    }
    if(x < 0) x += memob/b;
    return {b,x};
}
 
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    unsigned long long N,B; cin >> N >> B;
    auto [g,ans] = invgcd(N%B,B);
    if(g == 1) cout << ans << endl;
    else cout << "NaN" << endl; 
}