#pragma GCC optimize("Ofast")

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define all(x) begin(x), end(x)

template <typename T> bool chmin(T& x, T y) {
	return x > y ? (x = y, true) : false;
}
template <typename T> bool chmax(T& x, T y) {
	return x < y ? (x = y, true) : false;
}

struct IOST {
	IOST() {
		ios::sync_with_stdio(false);
		cin.tie(nullptr);
		cout << fixed << setprecision(20);
	}
} IOST;

__int128_t ps(string s) {
	__int128_t res = 0;
	for (char c : s) {
		res *= 10;
		res += c - '0';
	}
	return res;
}

void solve() {
	string s;
	cin >> s;
	auto n = ps(s);
	int b;
	cin >> b;
	n %= b;
	if (b == 1) {
		cout << "0\n";
		return;
	}
	rep(i, 1, b) {
		if ((n * i) % b == 1) {
			cout << i << "\n";
			return;
		}
	}
	cout << "NaN\n";
}

int main() {
	int t = 1;
	// cin >> t;
	rep(i, 0, t) solve();
}