Codeforces-solutions/Codeforces Round 988 (Div. 3)/C. Superultra's Favorite Permutation.cpp
2024-11-17 13:36:44 -03:00

141 lines
2.9 KiB
C++

/* Problem URL: https://codeforces.com/contest/2037/problem/C */
#include <bits/stdc++.h>
using namespace std;
#define V vector
#define rmin(a, b) a = min(a, b)
#define rmax(a, b) a = max(a, b)
#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
#define repv(i, v) for (auto &i : (v))
#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
#define sortv(v) sort(v.begin(), v.end())
#define all(v) (v).begin(), (v).end()
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vvvvi = vector<vvvi>;
using ll = long long;
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;
template<class v>
auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
os << vec[0];
for (size_t i = 1; i < vec.size(); i++) {
os << ' ' << vec[i];
}
os << '\n';
return os;
}
template<class v>
auto operator>>(istream &is, vector<v> &vec)->istream& {
for (auto &i : vec) {
is >> i;
}
return is;
}
template<class v>
auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
for (auto &i : vec) {
os << i[0];
for (size_t j = 1; j < i.size(); j++) {
os << ' ' << i[j];
}
os << '\n';
}
return os;
}
template<class v>
auto operator>>(istream &is, vector<vector<v>> &vec)->istream& {
for (auto &i : vec) {
for (auto &j : i) {
is >> j;
}
}
return is;
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(nullptr);
V<bool> isprime(1e5 * 4 + 1, true);
isprime[1] = false;
for (size_t i = 1; i <= (size_t)1e5 * 4; i++) {
if (!isprime[i]) {
continue;
}
for (size_t j = i * 2; j <= (size_t)1e5 * 4; j += i) {
isprime[j] = false;
}
}
int t;
cin >> t;
while (t--) {
int n;
cin >> n;
vi odd;
vi even;
for (size_t i = 1; i <= n; i++) {
if (i & 1) {
odd.push_back(i);
} else {
even.push_back(i);
}
}
int i = odd.size() - 1;
int j = 0;
while (i >= 0) {
j = even.size() - 1;
while (j >= 0 && isprime[odd[i] + even[j]]) {
j--;
}
if (j >= 0) {
break;
}
i--;
}
if (i < 0) {
cout << "-1\n";
continue;
}
for (size_t k = 0; k < odd.size(); k++) {
if (k != i) {
cout << odd[k] << ' ';
}
}
cout << odd[i] << ' ' << even[j] << ' ';
for (size_t k = 0; k < even.size(); k++) {
if (k != j) {
cout << even[k] << ' ';
}
}
cout << '\n';
}
}