#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
#define MAXN 510000
#define INF 0x3f3f3f3f
//AC
int n,m;
int num[MAXN];
typedef long long qword;
qword f[MAXN];
qword sum[MAXN];
inline qword sqr(int x)
{
        return x*x;
}
//f[i]=min(f[j]-2*sum[j]*sum[i]+sum[j]^2)+sum[i]^2+m
//f[i]=-2*sum[j]*sum[i] + f[j]+sum[j]^2 +sum[i]^2 + m
//  -2*sum[i]*sum[j] + sum[i]^2-f[i]+m == -f[j]-sum[j]^2
struct Point
{
        qword x,y;
        void init(qword xx,qword yy)
        {
                x=xx;y=yy;
        }
};
Point make_point (qword x,qword y)
{
        Point ret;
        ret.init(x,y);
        return ret;
}
qword xmul(Point p1,Point p2,Point p3)
{
        return (p2.x-p1.x)*(p3.y-p1.y)-(p2.y-p1.y)*(p3.x-p1.x);
}
double get_k(Point p1,Point p2)
{
        if (p1.x==p2.x)throw "error";
        return (double)(p2.y-p1.y)/(p2.x-p1.x);
}
struct Convex_Hall
{
        Point pl[MAXN];
        double kk[MAXN];
        int topl;
        void clear()
        {
                topl=-1;
        }

        Convex_Hall()
        {
                topl=-1;
        }
        void add_point(Point pp)
        {
                if (topl<1)
                {
                        pl[++topl]=pp;
                        if (topl==1&&pl[topl].x==pl[topl-1].x)
                        {
                                if (pl[topl].y<pl[topl-1].y)
                                {
                                        topl--;
                                        return ;
                                }else
                                {
                                        pl[topl--]=pp;
                                        return ;
                                }

                        }
                        if (topl==1)
                        {
                                kk[topl-1]=get_k(pl[topl-1],pl[topl]);
                        }
                        return ;
                }
                while (topl>=1&&xmul(pl[topl-1],pl[topl],pp)>=0)
                {
                        topl--;
                }
                pl[++topl]=pp;
                kk[topl-1]=get_k(pl[topl-1],pp);
        }
        void pm()
        {
                int i;
                for(i=0;i<=topl;i++)
                {
                        printf("(%d,%d) ",pl[i].x,pl[i].y);
                }
                printf("\n");
        }
        double get_maxb(double k)
        {
                int l,r,mid;
                if (topl==-1)throw "Error";
                if (topl==0)return pl[0].y-pl[0].x*k;
                if (k>kk[0])return pl[0].y-pl[0].x*k;
                if (k<kk[topl-1])return pl[topl].y-pl[topl].x*k;
                l=0,r=topl;
                while (l<r)
                {
                        mid=(l+r)>>1;
                        if (kk[mid-1]>=k&&kk[mid]<=k)
                        {
                                return pl[mid].y-pl[mid].x*k;
                        }
                        if (kk[mid-1]<k)
                        {
                                r=mid;
                        }else
                        {
                                l=mid;
                        }
                }
        }
}H;

int main()
{
        //freopen("input.txt","r",stdin);
        int i;
        while (~scanf("%d%d",&n,&m))
        {
                H.clear();
                for (i=1;i<=n;i++)
                {
                        scanf("%d",&num[i]);
                        sum[i]=sum[i-1]+num[i];
                }
                memset(f,INF,sizeof(f));
                /*        f[0]=0;
                        for (i=1;i<=n;i++)
                        {
                        for (j=0;j<i;j++)
                        {
                        if (f[j]>=INF)continue;
                        f[i]=min(f[i],f[j]+sqr(sum[i]-sum[j])+m);
                        }
                        }
                        for (i=1;i<=n;i++)cout<<f[i]<<" ";cout<<endl;
                 */        f[0]=0;
                H.add_point(make_point(sum[0],-sum[0]*sum[0]-f[0]));
                double k,b;
                for (i=1;i<=n;i++)
                {
                        k=-2*sum[i];
                        b=H.get_maxb(k);
                        f[i]=sum[i]*sum[i]+m-ceil(b);
                        H.add_point(make_point(sum[i],-sum[i]*sum[i]-f[i]));
                        //                cout<<f[i]<<" ";
                }
                cout<<f[n]<<endl;;
        }
        return 0;
}