/** gnu specific **/
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
/** contains everything I need in std **/
#include <bits/stdc++.h>

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(S) ((int)S.size())
#define FOR(i, st_, n) for(int i = st_; i < n; ++i)
#define RFOR(i, n, end_) for(int i = (n)-1; i >= end_; --i)
#define x first
#define y second
#define pb push_back
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ull, ull> pull;
using namespace __gnu_pbds;
typedef tree<ll, null_type, less<>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
using namespace std;
#ifdef ONPC
mt19937 rnd(228);
#else
mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
#endif


int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    ll n;
    cin >> n;
    vector<ll> ar(n);
    FOR(i,0,n)
        cin >> ar[i];
    ll res = 10000000000000;
    FOR(i,0,n)
        FOR(j,0,n)
        {
            ll cur = 0;
            FOR(k,0,n)
                cur += min((ar[i]-ar[k])*(ar[i]-ar[k]),(ar[j]-ar[k])*(ar[j]-ar[k]));
            res = min(res,cur);
        }
    cout << res;
}