#include<iostream>

#include<cstdio>

#include<cstring>

using namespace std;

typedef long long ll;

int const maxn=1e6+;

ll n,a,b,c,s[maxn],q[maxn],f[maxn];

ll y(int i){return f[i]+a*s[i]*s[i]-b*s[i];}

double slp(int i,int j){return (double)(y(j)-y(i))/(s[j]-s[i])//a;}//在这里/2/a

int main()

{

    scanf("%lld%lld%lld%lld",&n,&a,&b,&c);

    for(int i=;i<=n;i++)

        scanf("%lld",&s[i]),s[i]+=s[i-];

    int head=,tail=;

    for(int i=;i<=n;i++)

    {

        while(head<tail&&slp(q[head],q[head+])<=s[i])head++;//则这里没有*2*a,否则需要区分a的正负

        int j=q[head];

        double tmp=s[i]-s[j];

        f[i]=f[j]+a*tmp*tmp+b*tmp+c;

        while(head<tail&&slp(q[tail-],q[tail])>slp(q[tail-],i))tail--;//

        q[++tail]=i;

    }

    printf("%lld",f[n]);

    return ;

}