#pragma region Modefs
#define retword "-1"
#define MAXCOMB 202020
#define MOD 1000000007
#define EPS 1e-9;
#pragma endregion
//--MACROS---------------------------------
#pragma region Macros
#include <bits/stdc++.h>
#define SORT(x) sort((x).begin(), (x).end())
#define RSORT(x) sort((x).rbegin(), (x).rend())
#define ALL(x) (x).begin(), (x).end()
#define REV(x) reverse(ALL(x))
#define rep(i, n) for (ll i = 0; i < n; i++)
#define reps(i, m, n) for (ll i = m; i < n; i++)
#define repr(i, m, n) for (ll i = m; i >= n; i--)
#define SP << " " <<
#define INF2 1000000000000000037LL
#define INF  1000000007
#define lwb(x,n) distance(x.begin(),lower_bound(ALL(x),(n)))
#define upb(x,n) distance(x.begin(),upper_bound(ALL(x),(n)))
#define fora(i, ...) if(ll i = -1) for(__VA_ARGS__) if(i++, true)
#ifdef _MY_DEBUG
#define isdebug true
#define CHOOSE(a) CHOOSE2 a
#define CHOOSE2(a0,a1,a2,a3,x,...) x
#define debug_1(x1) cout<<#x1<<": "<<x1<<endl
#define debug_2(x1,x2) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<endl
#define debug_3(x1,x2,x3) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<endl
#define debug_4(x1,x2,x3,x4) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<", "#x4<<": "<<x4<<endl
#define de(...) CHOOSE((__VA_ARGS__,debug_4,debug_3,debug_2,debug_1,~))(__VA_ARGS__)
#else
#define isdebug false
#define de(...)
#endif
using namespace std;
using ll = long long;
using ld = long double;
const ld PI = 3.141592653589793238462643;
using P  = pair<ll,ll>;
using TP  = tuple<ll,ll,ll>;
ll intpow(ll a, ll b){ ll ans = 1; while(b){ if(b & 1) ans *= a; a *= a; b /= 2; } return ans; }
template<class T = ll> using v = vector<T>;
template<class T = ll> using vv = vector<vector<T>>;
template<class T = ll> using vvv = vector<vector<vector<T>>>;
template<class T> bool maxi(T &a, const T &b){ if(a<b){a=b;return 1;}return 0;}
template<class T> bool mini(T &a, const T &b){ if(b<a){a=b;return 1;}return 0;}
template<class T> ll sumer(const T& a){ return accumulate(ALL(a),0LL); }
template<class T> ll miner(const T& a){ return *min_element(ALL(a)); }
template<class T> ll maxer(const T& a){ return *max_element(ALL(a)); }
template<class T> ll bs(ll ok, ll ng, T checker){
    while( abs(ok-ng)>1 ){ ll mid = (ok+ng)/2; (checker(mid)?ok:ng) = mid; }
    return ok;
}
template<class T> ld bs2(ld ok, ld ng, T checker){
    rep(i,300){ ld mid = (ok+ng)/2; (checker(mid)?ok:ng) = mid; }
    return ok;
}
template<class T> void UNIQUE(vector<T> &a){ SORT(a);a.erase(unique(ALL(a)),a.end());}
template<class T, class U> ostream &operator<<(ostream &os, const pair<T,U> &pe) { os << pe.first << " " << pe.second; return os;}
template<class T> ostream &operator<<(ostream &os, const v<T> &ve) { rep(i,ve.size()) os<< (i?" ":"")<<ve[i]; return os;}
ll topbit(ll a) { return a==0?-1:63-__builtin_clzll(a);}
ll botbit(ll a) { return a==0?64:__builtin_ctzll(a);}
ll popcount(ll a) { return __builtin_popcountll(a);}
#define dame do {cout<< retword <<"\n"; return;} while(false)
template< int mod >
struct ModInt {
    ll x;
    ModInt() : x(0) {}
    ModInt(ll y) : x(y >= 0 ? ( y<mod ? y : y%mod ) : (mod - (-y) % mod) % mod) {}
    ModInt &operator+=(const ModInt &p) {
        if((x += p.x) >= mod) x -= mod;
        return *this;
    }
    ModInt &operator-=(const ModInt &p) {
        if((x += mod - p.x) >= mod) x -= mod;
        return *this;
    }
    ModInt &operator*=(const ModInt &p) {
        x = (int) (1LL * x * p.x % mod);
        return *this;
    }
    ModInt &operator/=(const ModInt &p) {
        *this *= p.inv();
        return *this;
    }
    ModInt operator-() const { return ModInt(-x); }
    ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }
    ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }
    ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }
    ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }
    bool operator==(const ModInt &p) const { return x == p.x; }
    bool operator!=(const ModInt &p) const { return x != p.x; }
    bool operator<(const ModInt &p) const {return x < p.x; }

    ModInt operator+(const ll &q) const {return ModInt(*this) += (ModInt)q; }
    ModInt operator-(const ll &q) const {return ModInt(*this) -= (ModInt)q; }
    ModInt operator*(const ll &q) const {return ModInt(*this) *= (ModInt)q; }
    ModInt operator/(const ll &q) const {return ModInt(*this) /= (ModInt)q; }
    bool operator==(const ll &q) const {return x == q; }
    bool operator!=(const ll &q) const {return x != q; }

    ModInt operator++(){ if(++x == mod) x = 0; return *this; }
    ModInt operator--(){ x = (x == 0 ? mod-1 : x-1); return *this; }
    ModInt operator++(int){ const ModInt res(*this); ++*this; return res; }
    ModInt operator--(int){ const ModInt res(*this); --*this; return res; }

    ModInt inv() const {
        int a = x, b = mod, u = 1, v = 0, t;
        while(b > 0) {
            t = a / b;
            swap(a -= t * b, b);
            swap(u -= t * v, v);
        }
        return ModInt(u);
    }

    ModInt pow(ll n, bool inv=false) const {
        ModInt ret(1), mul(x);
        while(n > 0) {
        if(n & 1) ret *= mul;
            mul *= mul;
            n >>= 1;
        }
        if(inv) ret=ret.inv();
        return ret;
    }

    friend ostream &operator<<(ostream &os, const ModInt &p) {
        return os << p.x;
    }
    friend istream &operator>>(istream &is, ModInt &a) {
        ll t;
        is >> t;
        a = ModInt< mod >(t);
        return (is);
    }
};
using mint = ModInt< MOD >;
mint mpow(ll x, ll n, bool inv=false) {
    mint ret(1), mul(x);
    while(n > 0) {
    if(n & 1) ret *= mul;
        mul *= mul;
        n >>= 1;
    }
    if(inv) ret=ret.inv();
    return ret;
}
mint fac[MAXCOMB], finv[MAXCOMB], inv[MAXCOMB];
void cinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    reps(i, 2, MAXCOMB){
        fac[i] = fac[i - 1] * i;
        inv[i] = inv[MOD%i] * -(MOD/i);
        finv[i] = finv[i - 1] * inv[i];
    }
}
mint com(int n, int k){ // 二項係数計算
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * finv[k] * finv[n-k];
}
#pragma endregion
//--GLOBAL---------------------------------
template<class T>
class LiChaoTree {
    T inf;
    int N;
    vector<ll> xs;
    vector<T> p, q;
    vector<bool> u;

    T get(T a, ll x, T b){ // return ax+b
        if(x==0) return b;
        /*
        if(inf/x<a) {return inf;}
        if(inf/x<-a) {return -inf;}
        */
        de(a*x+b);
        return a*x+b;
    }

    void _add_line(T a, T b, int k, int l, int r) {
        while(r-l > 0) { // a,bを更新材料として segment k, 範囲 [l,r)
            int m = (l + r) >> 1;
            if(!u[k]) { // まだ線分が入っていないなら入れる
                p[k] = a; q[k] = b;
                u[k] = true;
                return;
            }

            ll lx = xs[l], mx = xs[m], rx = xs[r-1];
            T pk = p[k], qk = q[k];
            /*
            bool left = (a*lx+b < pk*lx+qk);
            bool mid = (a*mx+b < pk*mx+qk);
            bool right = (a*rx+b < pk*rx+qk);
            */
            bool left = (get(a,lx,b) < get(pk,lx,qk));
            bool mid = (get(a,mx,b) < get(pk,mx,qk));
            bool right = (get(a,rx,b) < get(pk,rx,qk));

            if(left and right) { // 範囲内で直線が下にある
                p[k] = a; q[k] = b;
                return;
            }
            if(!left and !right) { // 範囲内で直線が上にある
                return;
            }
            if(mid) { // 中央で下なら上にもってくる
                swap(p[k], a);
                swap(q[k], b);
            }
            if(left != mid) { // クロスしている方を探索
                k = 2*k+1; r = m; // 0-index の SegTree
            } else {
                k = 2*k+2; l = m;
            }
        }
    }

    T _query(int k, ll x) {
        k += N - 1; // 最下位に移動
        T ret = u[k] ? get(p[k],x,q[k]) : INF2; // 最下位で計算
        while(k > 0) { // 最上位まで上がってそのうちの最小を計算
            k = (k - 1) / 2;
            if(u[k]) {
                T r = get(p[k],x,q[k]); // p[k]*x+q[k];
                ret = min(ret, r);
            }
        }
        return ret;
    }

public:
    LiChaoTree(vector<ll> &ps, T _inf): xs(ps), inf(_inf){
        N = 1; // xsに入っている場所は正確に探索される。[xs[i],xs[i+1])
        while(N < ps.size()) N <<= 1; // SegTreeのサイズを2の累乗に
        reps(i,ps.size(),N) xs.emplace_back(inf);  // 伸ばしたところををinfで埋める
        p.assign(N*2,0); // segmentのa
        q.assign(N*2,0); // segmentのb
        u.assign(N*2,false); // 1つ以上線分が追加されたかどうか判定
    }

    void add_line(T a, T b) {
        _add_line(a, b, 0, 0, N);
    }

    void add_segment_line(T a, T b, int l, int r) {
        ll l0 = l + N, r0 = r + N;
        ll s0 = l, t0 = r, sz = 1;
        while(l0 < r0) {
            if(r0 & 1) {
                --r0; t0 -= sz;
                _add_line(a, b, r0-1, t0, t0+sz);
            }
            if(l0 & 1) {
                _add_line(a, b, l0-1, s0, s0+sz);
                ++l0; s0 += sz;
            }
            l0 >>= 1; r0 >>= 1;
            sz <<= 1;
        }
    }

    ll query(int i) {
        return _query(i, xs[i]);
    }
};
//--MAIN-----------------------------------
void Main() {
    ll N,C; cin>>N>>C;
    v<> A(N);
    rep(i,N) cin>>A[i];
    auto B=A;
    LiChaoTree<ll> lct(A,1010101);
    lct.add_line(-A[0]*2,A[0]*A[0]+C);
    reps(i,1,N){
        ll x=lct.query(i);
        x+=A[i]*A[i];
        lct.add_line(-A[i]*2,A[i]*A[i]+C+x);
    }
    cout<< lct.query(N-1)+A[N-1]*A[N-1] <<"\n";
    
}
//--START----------------------------------
int main() {
    cin.tie(nullptr); ios_base::sync_with_stdio(false);
    // if(isdebug) {ifstream in("input.txt"); cin.rdbuf(in.rdbuf());}
    // if(isdebug) {ofstream out("output.txt"); cout.rdbuf(out.rdbuf());}
    cout << fixed << setprecision(15);
    // ll Qkai; cin>>Qkai; rep(QQ,Qkai) Main();
    Main();
}
//-----------------------------------------

Measured memory_bytes: 19448