#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <iostream>
#include <istream>
#include <iterator>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>
#include <tuple>
#include <iomanip>
#include <climits>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
//typedef pair<ll, ll> P;
#define rep(i, n) for(ll i = 0; i < (n); i++)
#define revrep(i, n) for(ll i = (n)-1; i >= 0; i--)
#define pb push_back
#define f first
#define s second
#define chmin(x, y) x = min(x, y);
#define chmax(x, y) x = max(x, y);

//const ll INFL = LLONG_MAX;//10^18 = 2^60
const ll INFL = 1LL<<60;
//const int INF = INT_MAX;
const ll INF = 1 << 30;//10^9
//ll MOD = 1000000007;
ll MOD = 998244353;

vector<ll> dy = {0, 1, 0, -1, 1, 1, -1, -1, 0};
vector<ll> dx = {1, 0, -1, 0, 1, -1, 1, -1, 0};

void pres(double A, ll x = 20){cout << fixed << setprecision(x) << A << endl;}
void BinarySay(ll x, ll y = 60){rep(i, y) cout << (x>>(y-1-i) & 1); cout << endl;}
ll cnt_bit(ll x){return __builtin_popcountll(x);}

ll pow_long(ll x, ll k){
  ll res = 1;
  while(k > 0){
    if(k % 2) res *= x;
    x *= x; k /= 2;
  }
  return res;
}

ll pow_mod(ll x, ll k){
  ll res = 1;
  while(k > 0){
    if(k % 2){
      res *= x; res %= MOD;
    }
    x *= x; x %= MOD;
    k /= 2;
  }
  return res;
}

ll inverse(ll x){return pow_mod(x, MOD - 2);};

ll gcd(ll a, ll b){
    if(b == 0) return a;
    return gcd(b, a % b);
}

ll lcm(ll x, ll y){
  ll res = x / gcd(x, y);
  res *= y;
  return res;
};


/*
//コンビネーション
const int MAXcomb = 200010;
ll fac[MAXcomb], finv[MAXcomb], inv[MAXcomb];
//facはn!,finvは1/n!
//invは逆元
void COMinit(){
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for(int i = 2; i < MAXcomb; i++){
        fac[i] = fac[i-1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD/i) % MOD;
        finv[i] = finv[i-1] * inv[i] % MOD;
    }
}
ll comb(int n, int k){
    if(n < k) return 0;
    if(n < 0 || k < 0) return 0;
    return fac[n] * finv[k] % MOD * finv[n-k] % MOD;
}

const int MAXkai = 200010;
ll kai_memo[MAXkai];
ll kai(ll N){
  if(kai_memo[N] != 0) return kai_memo[N];
  if(N <= 1) return 1;
  return kai_memo[N] = N * kai(N-1) % MOD;
}
*/


// Convex Hull Trick
/*
    追加クエリの直線の傾きが単調減少の場合

    - insert (a, b): add y = ax + b
    - query (x): min_i{a[i]*x + b}
*/
template<class T> struct CHT {
    using Line = pair<T, T>;
    deque<Line> lines;

    inline bool check(const Line &a, const Line &b, const Line &c) {
        return (double)(b.f - a.f) * 1. * (c.s - b.s) >= (double)(b.s - a.s) * 1. * (c.f - b.f);
    }

    inline ll get(int k, T x) {
        return (double)lines[k].f * x + lines[k].s;
    }

    void insert(T a, T b) {
        Line l(a, b);
        while (lines.size() >= 2
               && check(lines[(int)lines.size()-2], lines[(int)lines.size()-1], l)){
            lines.pop_back();
          }
        lines.push_back(l);
    }

    T query(T x) {
        int low = -1, high = (int)lines.size();
        while (high - low > 1) {
            int mid = (low + high) / 2;
            if (get(mid, x) >= get(mid + 1, x)) low = mid;
            else high = mid;
        }
        return get(high, x);
    }

    // クエリの単調性も成り立つ場合 (x が単調増加)
    T query_monotone(T x) {
        while (lines.size() >= 2 && get(0, x) >= get(1, x)) lines.pop_front();
        return lines[0].first * x + lines[0].second;
    }
};


ll N, C;
ll h[200010];
ll dp[200010];
void solve(){
  CHT<ll> cht;
  cin >> N >> C;
  rep(i, N) cin >> h[i];
  revrep(i, N) h[i] -= h[0];
  cht.insert(-h[0] * 2, dp[0] + h[0] * h[0]);
  for(ll i = 1; i < N; i++){
    ll m = cht.query_monotone(h[i]);
    dp[i] = C + m + h[i] * h[i];
    cht.insert(-h[i] * 2, dp[i] + h[i] * h[i]);
  }
  cout << dp[N-1] << endl;
}

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
}


Measured memory_bytes: 5632