#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 10;
const int INF = 0x3f3f3f3f;
int n, a[N], s[N], ans[N];

int main() {
    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> a[i], s[i] = s[i - 1] + a[i]; // 前缀和

    int mi = 0;
    for (int i = 1; i <= n; i++) {
        ans[i] = s[i] - mi;
        mi = min(mi, s[i]);
    }
    int res = -INF;
    for (int i = 1; i <= n; i++) res = max(res, ans[i]);
    cout << res << endl;
    return 0;
}