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

using i64 = long long;

using i128 = __int128_t;
istream& operator>>(istream &is, i128 &n) {
    string s;
    cin >> s;
    bool neg = false;
    if (s[0] == '-') {
        neg = true;
        s = s.substr(1);
    }
    n = 0;
    for (auto ch : s) {
        n = n * 10 + ch - '0';
    }
    if (neg) {
        n = -n;
    }
    return is;
}
ostream& operator<<(ostream &os, i128 n) {
    if (n < 0) {
        os << '-';
        n = -n;
    }
    if (n == 0) {
        os << 0;
    } else {
        string s;
        while (n > 0) {
            s += '0' + n % 10;
            n /= 10;
        }
        reverse(s.begin(), s.end());
        os << s;
    }
    return os;
}

i128 gcd(i128 x, i128 y) {
    return y == 0 ? x : gcd(y, x % y);
}

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);

    auto solve = [&]() {
        i128 n, b;
        cin >> n >> b;

        for (int i = 0; i < b; i++) {
            if ((n * i) % b == 1 % b) {
                cout << i << '\n';
                return;
            }
        }

        cout << "NaN" << '\n';
    };
    
    solve();
    
    return 0;
}