func_code_string: #include <bits/stdc++.h>   const int inf = INT_MAX;   const int MAX = 1e6 + 8;   const long long MOD = 998244353;   const int TOT_PRIMES = 1e6 + 9;   const int MAX_A = 71;   const int LN = 20;   using namespace std;   vector<int> adj[MAX];   int vis[MAX];   long long c = 0;   void dfs(int u) {     vis[u] = 1;     c = c + 1;     for (auto v : adj[u]) {       if (!vis[v]) {         dfs(v);       }     }   }   int main() {     int n;     cin >> n;     for (int i = 1; i <= n; i++) {       int x;       cin >> x;       adj[i].push_back(x);       adj[x].push_back(i);     }     vector<long long> res;     for (int i = 1; i <= n; i++) {       if (!vis[i]) {         dfs(i);         res.push_back(c);         c = 0;       }     }     sort(res.begin(), res.end());     long long ans = 0;     int m = res.size();     if (m == 1) {       cout << res[0] * res[0];       return 0;     }     ans = res[m - 1] + res[m - 2];     ans = ans * ans;     for (int i = 0; i < m - 2; i++) {       ans = ans + (res[i] * res[i]);     }     cout << ans;     return 0;   }   