#include "bits/stdc++.h" using namespace std; //諸機能 #pragma region MACRO #define ANSWER(x) cerr << "answer: "; cout << (x) << endl #define DOUBLE_ANSWER(x) cerr << "answer: "; cout << setprecision(10) << (double)(x) << endl #define REP(i,a,n) for(int i=(a); i<(int)(n); i++) #define RREP(i,a,n) for(int i=(int)(n); i>= a; i--) #define rep(i,n) REP(i,0,n) #define rrep(i,n) RREP(i,0,n) #define ALL(a) begin((a)),end((a)) #define FILL(a,n) for(auto &hoge : (a)) hoge = (n) #define mp make_pair #define EXIST(container, n) ((container).find((n)) != (container).end()) #define STOI(s,i,l) stoi(SUBSTR(s,i,l)) #define SUBSTR(s,i,l) string((s), (i), (l)) #define NPI_TO_RAD(x) (180.0*x/PI) #define RAD_TO_NPI(x) (PI/180.0*x) #pragma endregion //デバッグなどの支援 #pragma region CODING_SUPPORT #define DEBUG1(var0) { std::cerr << ( #var0 ) << "=" << ( var0 ) << endl; } #define DEBUG2(var0, var1) { std::cerr << ( #var0 ) << "=" << ( var0 ) << ", "; DEBUG1(var1); } #define DEBUG3(var0, var1, var2) { std::cerr << ( #var0 ) << "=" << ( var0 ) << ", "; DEBUG2(var1, var2); } #define DEBUG4(var0, var1, var2, var3) { std::cerr << ( #var0 ) << "=" << ( var0 ) << ", "; DEBUG3(var1, var2, var3); } #ifndef _DEBUG //デバッグでないなら、計算時間短縮のためにエラー出力を無効化 #define DEBUG1{} #define DEBUG2{} #define DEBUG3{} #define DEBUG4{} #endif //typedef(書き換える、書き足す可能性ある) #pragma region TYPE_DEF typedef long long ll; typedef pair pii; typedef pair pss; typedef pairpis; typedef pairpsi; typedef vector vs; typedef vector vi; #pragma endregion //諸々の定数(書き換える可能性ある) #pragma region CONST_VAL #define PI (2*acos(0.0)) #define EPS (1e-9) #define MOD (int)(1e9 + 7) #pragma endregion ll gcd(ll a, ll b) { if (a % b != 0) { return gcd(b, a% b); } else { return b; } } int main() { ll n; cin >> n; if (n == 1) { ANSWER(1); } else { ll tumitate = n*( n -1 ) / 2; ll x = gcd(n, tumitate); ANSWER(x); } return 0; }