#include <bits/stdc++.h>
#define LLI long long int
#define FOR(v, a, b) for(LLI v = (a); v < (b); ++v)
#define FORE(v, a, b) for(LLI v = (a); v <= (b); ++v)
#define REP(v, n) FOR(v, 0, n)
#define REPE(v, n) FORE(v, 0, n)
#define REV(v, a, b) for(LLI v = (a); v >= (b); --v)
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define ITR(it, c) for(auto it = (c).begin(); it != (c).end(); ++it)
#define RITR(it, c) for(auto it = (c).rbegin(); it != (c).rend(); ++it)
#define EXIST(c,x) ((c).find(x) != (c).end())
#define fst first
#define snd second
#define popcount __builtin_popcount
#define UNIQ(v) (v).erase(unique(ALL(v)), (v).end())
#define bit(i) (1LL<<(i))

#ifdef DEBUG
#include <misc/C++/Debug.cpp>
#else
#define dump(...) ((void)0)
#endif

#define gcd __gcd

using namespace std;
template <class T> constexpr T lcm(T m, T n){return m/gcd(m,n)*n;}

template <typename I> void join(ostream &ost, I s, I t, string d=" "){for(auto i=s; i!=t; ++i){if(i!=s)ost<<d; ost<<*i;}ost<<endl;}
template <typename T> istream& operator>>(istream &is, vector<T> &v){for(auto &a : v) is >> a; return is;}

template <typename T, typename U> bool chmin(T &a, const U &b){return (a>b ? a=b, true : false);}
template <typename T, typename U> bool chmax(T &a, const U &b){return (a<b ? a=b, true : false);}
template <typename T, size_t N, typename U> void fill_array(T (&a)[N], const U &v){fill((U*)a, (U*)(a+N), v);}

struct Init{
  Init(){
    cin.tie(0);
    ios::sync_with_stdio(false);
  }
}init;

/**
 * @note Comparator = less<T> : Minクエリ
 * @note Comparator = greater<T> : Maxクエリ
 */
template <typename T, typename Comparator> class LiChaoSegmentTree{
  using line = pair<T,T>;

  struct node{
    line l;
    node *left, *right;
    node(const line &l): l(l), left(nullptr), right(nullptr){}
  };

  const vector<T> xs;
  const int n;
  const T e;
  node *root;
  const Comparator cmp = Comparator();

  inline T chm(const T &a, const T &b) const{
    return cmp(a,b) ? a : b;
  }

public:
  LiChaoSegmentTree(const vector<T> xs, const T &e): xs(xs), n(xs.size()), e(e), root(nullptr){}

  inline T apply(const line &l, const T &x) const{
    return l.fst*x + l.snd;
  }

protected:
  node* add(node *t, const int left, const int right, line l){ // [l,r]
    if(!t) return new node(l);

    if(cmp(apply(t->l, xs[left]), apply(l, xs[left])) and cmp(apply(t->l, xs[right]), apply(l, xs[right]))){
      return t;
    }
    if(!cmp(apply(t->l, xs[left]), apply(l, xs[left])) and !cmp(apply(t->l, xs[right]), apply(l, xs[right]))){
      t->l = l;
      return t;
    }

    int mid = (left + right) / 2;

    if(!cmp(apply(t->l, xs[mid]), apply(l, xs[mid]))) swap(t->l, l);
    if(!cmp(apply(t->l, xs[left]), apply(l, xs[left]))){
      t->left = add(t->left, left, mid, l);
    }else{
      t->right = add(t->right, mid+1, right, l);
    }

    return t;
  }

public:
  inline void add(T a, T b){
    root = add(root, 0, n-1, make_pair(a,b));
  }

protected:
  T query(node *t, const int left, const int right, const int i) const{
    if(!t) return e;
    if(right == left) return apply(t->l, xs[i]);
    int mid = (left + right) / 2;
    if(i <= mid) return chm(apply(t->l, xs[i]), query(t->left, left, mid, i));
    else return chm(apply(t->l, xs[i]), query(t->right, mid+1, right, i));
  }
  
public:
  inline T query(const T &x) const{
    int t = lower_bound(ALL(xs), x) - xs.begin();
    return query(root, 0, n-1, t);
  }
};












LLI dp[201000];

int main(){
  LLI N,C;
  while(cin >> N >> C){

    vector<LLI> h(N); cin >> h;

    /*
      dp[i]
      = min(dp[j] + (hi-hj)^2 + C)
      = min(dp[j] + hi^2 - 2*hi*hj + hj^2 + C)
      = min(-2*hj*hi + hj^2 + dp[j]) + hi^2 + C
    */

    LiChaoSegmentTree<LLI, less<LLI>> cht(h,LLONG_MAX);

    dp[0] = 0;
    cht.add(-2*h[0],h[0]*h[0]+dp[0]);

    FOR(i,1,N){
      dp[i] = cht.query(h[i]) + h[i]*h[i] + C;
      cht.add(-2*h[i],h[i]*h[i]+dp[i]);
    }

    cout << dp[N-1] << endl;

  }
  
  return 0;
}


Measured memory_bytes: 14308