#include <iostream>
#include <bits/stdc++.h>

using namespace std;
int maxx = 0;
int a[1000];
int n;
int f(int x,int cursum) {
    maxx= max(maxx,cursum);
    for (int i = x+1; i < n;i++) {
        if (a[x] < a[i]) {
            f(i,cursum+a[i]);
        }
    }
}
int main() {
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(100);
    cin >> n;
    for (int i = 0; i < n;i++) cin >> a[i];
    int lastmax = 0;
    for (int i = 0; i < n;i++) {
        if (a[lastmax] >= a[i]) {
            f(i,a[i]);
        } else lastmax = i;
    }
    cout << maxx;

















}