#include<bits/stdc++.h>
#define INF LLONG_MAX-1
using namespace std;
typedef long long ll;

ll a[100001];
int main(){
	ll n;
	ll cnt = 0;
	scanf("%lld", &n);
	for (ll i = 0; i < n; i++){
		scanf("%lld", &a[i]);
		cnt += a[i];
	}
	ll Max = cnt;
	ll w = 0;
	for (ll i = 0; i < n; i++){
		cnt -= a[i];
		if (Max < cnt) {
			w = i;
			Max = cnt;
		}
	}
	cnt = Max;
	for (ll i = n - 1; i > w; i--){
		cnt -= a[i];
		Max = max(Max, cnt);
	}
	printf("%lld\n", Max);
	return 0;
}