using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using SB = System.Text.StringBuilder;
//using System.Threading.Tasks;
//using System.Text.RegularExpressions;
//using System.Globalization;
//using System.Diagnostics;
using static System.Console;
using System.Numerics;
using static System.Math;
using pair = Pair<int, int>;

class Program
{
    static void Main()
    {
        //SetOut(new StreamWriter(OpenStandardOutput()) { AutoFlush = false });
        new Program().solve();
        Out.Flush();
    }
    readonly Scanner cin = new Scanner();
    readonly int[] dd = { 0, 1, 0, -1, 0 }; //→↓←↑
    readonly int mod = 1000000007;
    readonly int dom = 998244353;
    bool chmax<T>(ref T a, T b) where T : IComparable<T> { if (a.CompareTo(b) < 0) { a = b; return true; } return false; }
    bool chmin<T>(ref T a, T b) where T : IComparable<T> { if (b.CompareTo(a) < 0) { a = b; return true; } return false; }

    void solve()
    {
        int N = cin.nextint;
        var C = cin.nextlong;
        var dp = new long[N];
        var CHT = new LiChaoTree(1000000);
        var H = cin.scanlong;
        CHT.Add(-2 * H[0], H[0] * H[0]);
        for (int j = 1; j < N; j++)
        {
            dp[j] = H[j] * H[j] + C + CHT[(int)H[j]];
            CHT.Add(-2 * H[j], dp[j] + H[j] * H[j]);
        }
        WriteLine(dp[N - 1]);
    }

}

class LiChaoTree
{
    class Linear
    {
        public long a, b;
        public Linear(long a, long b) { this.a = a; this.b = b; }
        public long this[long x] => a * x + b;
    }
    readonly int n;
    Linear[] tr;
    readonly Linear exnum = new Linear(0, long.MaxValue);
    readonly long[] X;

    /// <summary>
    /// LiChaoTreeによる動的CHT
    /// </summary>
    /// <param name="M">x座標の最大値</param>
    public LiChaoTree(int M)
    {
        M++; n = 1; while (n < M) n <<= 1;
        tr = new Linear[(n << 1) - 1];
        for (int i = 0; i < tr.Length; i++) tr[i] = exnum;
        X = new long[n];
        for (int i = 0; i < X.Length; i++) X[i] = i;
    }
    /// <summary>
    /// LiChaoTreeによるクエリ先読み動的CHT
    /// </summary>
    /// /// <param name="M">x座標の最大値</param>
    /// <param name="Q">ソート済みであるX座標のクエリ配列</param>
    public LiChaoTree(long M, long[] Q)
    {
        n = 1; while (n < Q.Length) n <<= 1;
        tr = new Linear[(n << 1) - 1];
        for (int i = 0; i < tr.Length; i++) tr[i] = exnum;
        X = new long[n];
        for (int i = 0; i < Q.Length; i++) X[i] = Q[i];
        for (int i = Q.Length; i < X.Length; i++) X[i] = M << 1;
    }

    /// <summary>
    /// ある座標xにおけるy座標の最小値
    /// </summary>
    /// <param name="j">そのx座標のインデックス</param>
    /// <returns>y座標の最小値 long値</returns>
    public long this[int j]
    {
        get
        {
            var x = X[j];
            int i = j + n - 1;
            var ret = tr[i][x];
            while (i > 0) { i = i - 1 >> 1; ret = Min(ret, tr[i][x]); }
            return ret;
        }
    }
    /// <summary>
    /// 直線 y=ax+b を追加
    /// </summary>
    /// <param name="a">傾きa</param>
    /// <param name="b">切片b</param>
    public void Add(long a, long b) => Add(0, 0, n, new Linear(a, b));
    void Add(int k, int l, int r, Linear f)
    {
        var lx = X[l];
        var rx = X[r - 1];
        var left = f[lx] < tr[k][lx];
        var right = f[rx] < tr[k][rx];

        if (!left && !right) return;
        if (left && right) { tr[k] = f; return; }

        int m = l + r >> 1;
        var mx = X[m];
        var mid = f[mx] < tr[k][mx];
        if (mid) { Linear tmp = f; f = tr[k]; tr[k] = tmp; }

        if (left != mid) Add(k << 1 | 1, l, l + r >> 1, f);
        else Add(k + 1 << 1, l + r >> 1, r, f);
    }
}

static class Ex
{
    public static void join<T>(this IEnumerable<T> values, string sep = " ") => WriteLine(string.Join(sep, values));
    public static string concat<T>(this IEnumerable<T> values) => string.Concat(values);
    public static string reverse(this string s) { var t = s.ToCharArray(); Array.Reverse(t); return t.concat(); }

    public static int lower_bound<T>(this IList<T> arr, T val) where T : IComparable<T>
    {
        int low = 0, high = arr.Count;
        int mid;
        while (low < high)
        {
            mid = ((high - low) >> 1) + low;
            if (arr[mid].CompareTo(val) < 0) low = mid + 1;
            else high = mid;
        }
        return low;
    }
    public static int upper_bound<T>(this IList<T> arr, T val) where T : IComparable<T>
    {
        int low = 0, high = arr.Count;
        int mid;
        while (low < high)
        {
            mid = ((high - low) >> 1) + low;
            if (arr[mid].CompareTo(val) <= 0) low = mid + 1;
            else high = mid;
        }
        return low;
    }
}

class Pair<T, U> : IComparable<Pair<T, U>> where T : IComparable<T> where U : IComparable<U>
{
    public T f; public U s;
    public Pair(T f, U s) { this.f = f; this.s = s; }
    public int CompareTo(Pair<T, U> a) => f.CompareTo(a.f) != 0 ? f.CompareTo(a.f) : s.CompareTo(a.s);
    public override string ToString() => $"{f} {s}";
}

class Scanner
{
    string[] s; int i;
    readonly char[] cs = new char[] { ' ' };
    public Scanner() { s = new string[0]; i = 0; }
    public string[] scan => ReadLine().Split();
    public int[] scanint => Array.ConvertAll(scan, int.Parse);
    public long[] scanlong => Array.ConvertAll(scan, long.Parse);
    public double[] scandouble => Array.ConvertAll(scan, double.Parse);
    public string next
    {
        get
        {
            if (i < s.Length) return s[i++];
            string st = ReadLine();
            while (st == "") st = ReadLine();
            s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
            i = 0;
            return next;
        }
    }
    public int nextint => int.Parse(next);
    public long nextlong => long.Parse(next);
    public double nextdouble => double.Parse(next);
}


Measured memory_bytes: 64100