#include <bits/stdc++.h>

using namespace std;

const int maxn = 5e5 + 50;

int n , A[maxn] , tail;
long long Sum[maxn] , T[maxn] , ans;
pair < long long , long long > p1[maxn] , p2[maxn] , Convex[maxn];

long long Compute( int l , int r ){
	return Sum[r] * Sum[r] - Sum[r] * Sum[l - 1] - T[r] + T[l - 1];
}

double Cross( pair < long long , long long > x , pair < long long , long long > y ){
	return 1. * x.first * y.second - 1. * x.second * y.first;
}

void ins1( pair < long long , long long > c ){
	while( tail > 1 && Cross( make_pair( Convex[tail - 1].first - Convex[tail - 2].first , Convex[tail - 1].second - Convex[tail - 2].second ) , make_pair( c.first - Convex[tail - 1].first , c.second - Convex[tail - 1].second ) ) >= 0 )
		-- tail;
	Convex[tail ++] = c;
}

void ins2( pair < long long , long long > c ){
	while( tail > 1 && Cross( make_pair( Convex[tail - 1].first - Convex[tail - 2].first , Convex[tail - 1].second - Convex[tail - 2].second ) , make_pair( c.first - Convex[tail - 1].first , c.second - Convex[tail - 1].second ) ) <= 0 )
		-- tail;
	Convex[tail ++] = c;
}

void Gao( int l , int r ){
	int mid = l + r >> 1;
	for(int i = l ; i <= mid ; ++ i)
		p1[i] = { Sum[i] , T[i] };
	for(int i = mid + 1 ; i <= r ; ++ i)
		p2[i] = { Sum[i] , T[i] };
	sort( p1 + l , p1 + mid + 1 );
	sort( p2 + mid + 1 , p2 + r + 1 );
	tail = 0;
	for(int i = mid + 1 , j = l ; i <= r ; ++ i){
		while( j <= mid && p1[j].first <= p2[i].first ){
			ins1( p1[j] );
			++ j;
		}
		int l = 0 , r = tail - 1;
		while( l < r ){
			int mid = l + r >> 1;
			long long cost1 = p2[i].first * p2[i].first - p2[i].first * Convex[mid].first - p2[i].second + Convex[mid].second;
			long long cost2 = p2[i].first * p2[i].first - p2[i].first * Convex[mid + 1].first - p2[i].second + Convex[mid + 1].second;
			if( cost1 >= cost2 ) r = mid;
			else l = mid + 1;
		}
		ans = max( ans , p2[i].first * p2[i].first - p2[i].first * Convex[l].first - p2[i].second + Convex[l].second );
	}
	sort( p1 + l , p1 + mid + 1 , greater < pair < long long , long long > >() );
	sort( p2 + mid + 1 , p2 + r + 1 , greater < pair < long long , long long > >() );
	tail = 0;
	for(int i = mid + 1 , j = l ; i <= r ; ++ i){
		while( j <= mid && p1[j].first >= p2[i].first ){
			ins2( p1[j] );
			++ j;
		}
		int l = 0 , r = tail - 1;
		while( l < r ){
			int mid = l + r >> 1;
			long long cost1 = p2[i].first * p2[i].first - p2[i].first * Convex[mid].first - p2[i].second + Convex[mid].second;
			long long cost2 = p2[i].first * p2[i].first - p2[i].first * Convex[mid + 1].first - p2[i].second + Convex[mid + 1].second;
			if( cost1 >= cost2 ) r = mid;
			else l = mid + 1;
		}
		ans = max( ans , p2[i].first * p2[i].first - p2[i].first * Convex[l].first - p2[i].second + Convex[l].second );
	}
}

void Solve( int l , int r ){
	if( l >= r ) return;
	else{
		int mid = l + r >> 1;
		Gao( l , r );
		Solve( l , mid );
		Solve( mid + 1 , r );
	}
}

int main( int argc , char * argv[] ){
	scanf( "%d" , & n );
	for(int i = 1 ; i <= n ; ++ i){
		scanf( "%d" , A + i );
		Sum[i] = Sum[i - 1] + A[i];
		T[i] = T[i - 1] + 1ll * A[i] * Sum[i];
	}
	Solve( 0 , n );
	printf( "%lld\n" , ans );
	return 0;
}