//#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <math.h>
#include <set>
#include <map>
#include <queue>
#include <deque>
#include <stack>
#include <iostream>

#define INF 1e18 + 9



typedef long long ll;


using namespace std;

ll a[100005], dp[200005][3];

int n;



int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n;
    for(int i = 0; i < n; i++)
        cin >> a[i];

    dp[0][1] = dp[0][0] = dp[0][2] = 0;


    for (int i = 1; i < n; i++)
    {
        ll mn = min(dp[i - 1][0], min(dp[i - 1][1], dp[i - 1][2]));
        dp[i][0] = mn + abs(a[i] - a[i - 1]) * abs(a[i] - a[i - 1]);


        if (i >= 2)
        {
            ll mn2 = min(dp[i - 2][0], min(dp[i - 2][1], dp[i - 2][2]) );
            dp[i][1] = mn2 + abs(a[i - 2] - a[i]) * abs(a[i - 2] - a[i]) * 3;
        }
        else
            dp[i][1] = INF;

        if (i >= 3)
        {
            dp[i][2] = mn + abs(a[i - 1] - a[i - 2]) * abs(a[i - 1] - a[i - 2]) + abs(a[i - 2] - a[i]) * abs(a[i - 2] - a[i]) * 3;
        }
        else
            dp[i][2] = INF;

    }



    cout << min(dp[n - 1][0], min(dp[n - 1][1], dp[n - 1][2]));




    return 0;
}