using System;
using System.Collections.Generic;
using System.Collections;
using System.Collections.Specialized;
using System.Linq;
using System.Text;
using System.IO;
using System.Reflection;
using static System.Math;
using System.Numerics;
static class Program{
	const int mod=(int)1e9+7;
	static void Main(){
		Sc sc=new Sc();
		var s=sc.La;
		var h=sc.La;
		var dp=new long[s[0]+1];
		var cht=new Cht(false);
		cht.Add(0,-h[0]*2,h[0]*h[0]);
		for(int i = 1;i<s[0];i++) {
			dp[i]=cht.Get1(h[i]).Item2+h[i]*h[i]+s[1];
			cht.Add(i,-h[i]*2,dp[i]+h[i]*h[i]);
		}
		Console.WriteLine(dp[s[0]-1]);
	}
}
public class Cht{ 
	private List<Dt> li;
	private bool bo;
	private int k=0;
	public class Dt{
		public int n;
		public long a,b;
		public Dt(int n,long a,long b){this.n=n;this.a=a;this.b=b;}
	}
	public Cht(bool bo){
		this.bo=bo;
		li=new List<Dt>();
	}
	public void Add(int n,long a,long b){
		int m=li.Count-1;
		while(m>0&&(li[m].a-li[m-1].a)*(b-li[m].b)>=(li[m].b-li[m-1].b)*(a-li[m].a)){
			li.RemoveAt(m);
			m--;
		}
		li.Add(new Dt(n,a,b));
	}
	public Tuple<int,long> Get1(long n){
		int lb=-1,ub=li.Count-1,mid=0;
		while(lb+1!=ub){
			mid=(ub+lb)>>1;
			if(li[mid].a*n+li[mid].b>=li[mid+1].a*n+li[mid+1].b){lb=mid;}
			else{ub=mid;}
		}
		return Tuple.Create(li[ub].n,li[ub].a*n+li[ub].b);
	}
	public Tuple<int,long> Get2(long n){
		while(k<li.Count-1&&li[k].a*n+li[k].b>=li[k+1].a*n+li[k+1].b){k++;}
		return Tuple.Create(li[k].n,li[k].a*n+li[k].b);
	}
}
public class Sc{
	public int I{get{return int.Parse(Console.ReadLine());}}
	public long L{get{return long.Parse(Console.ReadLine());}}
	public double D{get{return double.Parse(Console.ReadLine());}}
	public string S{get{return Console.ReadLine();}}
	public int[] Ia{get{return Array.ConvertAll(Console.ReadLine().Split(),int.Parse);}}
	public long[] La{get{return Array.ConvertAll(Console.ReadLine().Split(),long.Parse);}}
	public double[] Da{get{return Array.ConvertAll(Console.ReadLine().Split(),double.Parse);}}
	public string[] Sa{get{return Console.ReadLine().Split();}}
	public object[] Oa{get{return Console.ReadLine().Split();}}
	public int[] Ia2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),int.Parse);}}
	public int[] Ia3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),int.Parse);}
	public int[] Ia3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),int.Parse);}
	public long[] La2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),long.Parse);}}
	public long[] La3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),long.Parse);}
	public long[] La3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),long.Parse);}
	public double[] Da2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),double.Parse);}}
	public double[] Da3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),double.Parse);}
	public double[] Da3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),double.Parse);}
	public T[] Arr<T>(int n,Func<T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f();}return a;}
	public T[] Arr<T>(int n,Func<int,T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(i);}return a;}
	public T[] Arr<T>(int n,Func<string[],T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(Console.ReadLine().Split());}return a;}
	public T[] Arr<T>(int n,Func<int,string[],T> f){var a=new T[n];for(int i=0;i<n;i++){a[i]=f(i,Console.ReadLine().Split());}return a;}
}

Measured memory_bytes: 40664