#include <bits/stdc++.h>
using namespace std;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define FOR(i, begin, end) for(int i=(begin);i<(end);i++)
#define REP(i, n) FOR(i,0,n)
#define IFOR(i, begin, end) for(int i=(end)-1;i>=(begin);i--)
#define IREP(i, n) IFOR(i,0,n)
#define Sort(v) sort(v.begin(), v.end())
#define Reverse(v) reverse(v.begin(), v.end())
#define all(v) v.begin(),v.end()
#define SZ(v) ((int)v.size())
#define Lower_bound(v, x) distance(v.begin(), lower_bound(v.begin(), v.end(), x))
#define Upper_bound(v, x) distance(v.begin(), upper_bound(v.begin(), v.end(), x))
#define Max(a, b) a = max(a, b)
#define Min(a, b) a = min(a, b)
#define bit(n) (1LL<<(n))
#define bit_exist(x, n) ((x >> n) & 1)
#define debug(x) cout << #x << "=" << x << endl;
#define vdebug(v) cout << #v << "=" << endl; REP(i_debug, v.size()){ cout << v[i_debug] << ","; } cout << endl;
#define mdebug(m) cout << #m << "=" << endl; REP(i_debug, m.size()){ REP(j_debug, m[i_debug].size()){ cout << m[i_debug][j_debug] << ","; } cout << endl;}
#define pb push_back
#define f first
#define s second
#define int long long
#define INF 1000000000000000000
template<typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; }
template<typename T> ostream &operator<<(ostream &os, vector<T> &v){ for(int i = 0; i < v.size(); i++) { cout << v[i]; if(i != v.size() - 1) cout << endl; }; return os; }
template<typename T> void Out(T x) { cout << x << endl; }
template<typename T1, typename T2> void Ans(bool f, T1 y, T2 n) { if(f) Out(y); else Out(n); }

using vec = vector<int>;
using mat = vector<vec>;
using Pii = pair<int, int>;
using PiP = pair<int, Pii>;
using PPi = pair<Pii, int>;
using bools = vector<bool>;
using pairs = vector<Pii>;

//int dx[4] = {1,0,-1,0};
//int dy[4] = {0,1,0,-1};
//char d[4] = {'D','R','U','L'};

const int mod = 1000000007;
//const int mod = 998244353;
#define Add(x, y) x = (x + (y)) % mod
#define Mult(x, y) x = (x * (y)) % mod

//max: 追加クエリの傾きは広義単調増加と仮定
//min: 追加クエリの傾きは広義単調減少と仮定
//minを基準にコードを作成している
struct CHT
{
    using T = int;
    using type_check = __int128;
    using P = pair<T, T>;
    vector<P> lines;
    bool calcMax = true;

    CHT(bool calcMax = true): calcMax(calcMax) {};

    T f(int i, T x){
        return lines[i].first * x + lines[i].second;
    }

    //f2を取り除いて良いか
    bool check(P l1, P l2, P l3){
        type_check p1 = (type_check)(l1.first - l2.first) * (type_check)(l2.second - l3.second);
        type_check p2 = (type_check)(l2.first - l3.first) * (type_check)(l1.second - l2.second);
        return p1 >= p2;
    }

    void add(T a, T b){
        if(calcMax) { a *= -1; b *= -1; }

        P tmp = P(a, b);
        while(lines.size() >= 2 && check(lines[lines.size() - 2], lines[lines.size() - 1], tmp))
            lines.pop_back();
        
        if(lines.size()){
            if(tmp.first > (lines.back()).first) assert(false);
            if(tmp >= lines.back()) return;
        }

        lines.push_back(tmp);
    }

    T get(T x){
        int i1 = -1, i2 = lines.size() - 1;
        while(i2 - i1 > 1){
            int i = (i1 + i2) / 2;
            if(f(i, x) < f(i + 1, x)) i2 = i;
            else i1 = i;
        }
        T res = f(i2, x);
        if(calcMax) res *= -1;
        return res;
    }
};


signed main(){

    int N, C; cin >> N >> C;
    vec h(N); cin >> h;
    vec dp(N);
    CHT cht(false);
    dp[0] = 0;
    FOR(i, 1, N){
        cht.add(-2 * h[i - 1], dp[i - 1] + h[i - 1] * h[i - 1] + C);
        dp[i] = cht.get(h[i]) + h[i] * h[i];
    }
    Out(dp[N - 1]);

    return 0;
}


Measured memory_bytes: 9584