#include <bits/stdc++.h>   using namespace std;   #pragma GCC optimize( O3 )   template <class c>   struct rge {     c b, e;   };   template <class c>   rge<c> range(c i, c j) {     return rge<c>{i, j};   }   template <class c>   auto dud(c* x) -> decltype(cerr << *x, 0);   template <class c>   char dud(...);   struct debug {     template <class c>     debug& operator<<(const c&) {       return *this;     }   };   int main();   void file() {}   void time() {}   const int INF = 1e9 + 99;   using ll = long long int;   using pii = pair<int, int>;   using vec = vector<int>;   int main() {     ios_base::sync_with_stdio(0);     ;     ll n;     cin >> n;     vector<ll> v(n);     for (ll& x : v) {       cin >> x;     }     sort(v.begin(), v.end());     ll i = 0, j = n - 1;     ll x = 0, y = 0;     bool ok = false;     while (i <= j) {       if (ok) {         x += v[i];         i++;       } else {         y += v[j];         j--;       }       ok ^= 1;     }     ll ans = x * x + y * y;     cout << ans << endl;     return 0;   }   