#include<bits/stdc++.h> namespace { #pragma GCC diagnostic ignored "-Wunused-function" #include<atcoder/all> #pragma GCC diagnostic warning "-Wunused-function" using namespace std; using namespace atcoder; #define rep(i,n) for(int i = 0; i < (int)(n); i++) #define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--) #define all(x) begin(x), end(x) #define rall(x) rbegin(x), rend(x) template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; } template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; } using ll = long long; using P = pair<int,int>; using VI = vector<int>; using VVI = vector<VI>; using VL = vector<ll>; using VVL = vector<VL>; template<class T> vector<pair<T, int>> factorize(T x) { vector<pair<T, int>> res; for(T p = 2; p * p <= x; p++) { int cnt = 0; while(x % p == 0) x /= p, cnt++; if (cnt) res.emplace_back(p, cnt); } if (x > 1) res.emplace_back(x, 1); return res; } long long reduced_totient(long long a) { long long res = 1; for(auto [p, cnt]: factorize(a)) { if (p == 2) { res = cnt <= 2 ? 1LL << (cnt - 1) : 1LL << (cnt - 2); continue; } long long phi = p - 1; for(int i = cnt - 1; i > 0; i--) phi *= p; res = lcm(res, phi); } return res; } ll calc_ord(ll x, ll m) { assert(m >= 1 && gcd(x, m) == 1); if (m <= 2) return 1; x %= m; if (x < 0) x += m; auto fs = factorize(reduced_totient(m)); int n = fs.size(); vector<ll> dp(n), pe(n); for (int i = 0; auto [p, e] : fs) { ll v = 1; while (e--) v *= p; pe[i++] = v; } dp[0] = x; int k = bit_ceil(0U + n); while (k != 1) { int k2 = k / 2; for (int l = 0; l + k2 < n; l += k) { int c = l + k2, r = min(n, l + k); ll v = 1; for (int i = l; i < c; i++) v *= pe[i]; dp[c] = pow_mod(dp[l], v, m); v = 1; for (int i = c; i < r; i++) v *= pe[i]; dp[l] = pow_mod(dp[l], v, m); } k = k2; } ll res = 1; for (int i = 0; i < n; i++) { ll xi = dp[i]; int p = fs[i].first; while (xi != 1) xi = pow_mod(xi, p, m), res *= p; } return res; } } int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; cout << calc_ord(10, n) << '\n'; }