func_code_string: #include <bits/stdc++.h>   using namespace std;   const int inf = 1e9 + 7;   int arr[200005];   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n;     cin >> n;     if (n % 2 == 0) {       cout <<  NO n ;       return 0;     }     int flag = 1, ct = 1;     for (int i = 1; i <= n; i++) {       if (flag) {         arr[i] = ct;         arr[n + i] = ct + 1;         flag = 0;       } else {         arr[i] = ct + 1;         arr[n + i] = ct;         flag = 1;       }       ct += 2;     }     cout <<  YES n ;     for (int i = 1; i <= 2 * n; i++) {       cout << arr[i] <<    ;     }   }   