func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     vector<int> v;     bool g;     int n, m[5001] = {0}, x;     cin >> n;     if (n % 2 == 1) {       v.push_back(1);       m[1] = 1;     } else {       v.push_back(2);       m[2] = 1;     }     while (true) {       g = false;       for (int i = 1; i <= n; i++) {         if (!m[i] && abs(v.back() - i) != 1) {           v.push_back(i);           m[i] = 1;           g = true;         }       }       if (!g) break;     }     cout << v.size() <<   n ;     for (int i = 0; i < v.size(); i++) cout << v[i] <<    ;     return 0;   }   