#include<iostream>
#include<algorithm>
#include<deque>
using namespace std;
typedef long long ll;
ll s[1000010],d[1000010],p[1000010],p2[1000010];
deque<ll> a,b,c;
int cnt=0;
void push(ll n,ll m){
int sz=a.size();
while( sz>1 && (b[0]-b[1])*(a[0]-n) < (m-b[0])*(a[1]-a[0]) ){
sz--;
a.pop_front();
b.pop_front();
c.pop_front();
}
a.push_front(n);
b.push_front(m);
c.push_front(cnt++);
}
ll query(ll x,ll y){
if(a.size()==1)return a[0]*x+b[0]+y;
int lo=0,hi=a.size(),mid;
while(lo+1<hi){
mid=(lo+hi)/2;
if(b[mid]-b[mid-1]<x*(a[mid-1]-a[mid])){
hi=mid;
}
else{
lo=mid;
}
}
return a[lo]*x+b[lo]+y;
}
int main(){
ll n,ans=0;
cin>>n;
for(int i=1;i<=n;i++){
cin>>s[i];
p[i]=p[i-1]+s[i];
p2[i]=p2[i-1]+i*s[i];
}
push(-1,-p2[1]+p[1]);
for(ll i=1;i<=n;i++){
d[i]=p2[i];
d[i]=max(d[i],query(p[i],p2[i]));
push(-(i+1),d[i]-p2[i+1]+(i+1)*p[i+1]);
}
cout<<d[n];
}
