cp/cses/permutations/solution.cc

76 lines
1.3 KiB
C++

#include <bits/stdc++.h> // {{{
// https://codeforces.com/blog/entry/96344
#pragma GCC optimize("O2,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
using namespace std;
template <typename T>
constexpr T MIN = std::numeric_limits<T>::min();
template <typename T>
constexpr T MAX = std::numeric_limits<T>::max();
template <typename T>
[[nodiscard]] static T sc(auto &&x) {
return static_cast<T>(x);
}
template <typename T>
[[nodiscard]] static T sz(auto &&x) {
return static_cast<T>(x.size());
}
using ll = long long;
using ld = long double;
template <typename T>
using vec = std::vector<T>;
template <typename T, size_t N>
using arr = std::array<T, N>;
#define ff first
#define ss second
#define eb emplace_back
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
// }}}
void solve() {
int n;
cin >> n;
/*
n= 5;
1 4 2 5 3
1 4 2 5 3 6
1 7 2 6 3 5 4
41325
*/
if (n == 1) {
cout << 1 << endl;
} else if (n <= 3) {
cout << "NO SOLUTION\n";
} else {
for (int cur = n & 1 ? n - 1 : n; cur > 4; cur -= 2) {
cout << cur << ' ';
}
cout << "2 4";
for (int cur = 1; cur <= n; cur += 2) {
cout << ' ' << cur;
}
}
}
int main() { // {{{
cin.tie(nullptr)->sync_with_stdio(false);
solve();
return 0;
}
// }}}