#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define fix(n) cout<; const ll MOD = 1000000007; // 10^9 + 7 const int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1}; const int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1}; ll gcd(ll a, ll b) { if (a < b) return gcd(b, a); if (b == 0) return a; return gcd(b, a % b); } void solve() { ll N; cin >> N; outl(gcd(N, N*(N-1)/2)); } signed main() { cin.tie(0); ios::sync_with_stdio(false); srand((unsigned)time(NULL)); fix(12); solve(); }