#include <bits/stdc++.h>

using namespace std;

int a[101] = {0};
int f[101] = {0};
int n;
//用一层循环获取连续最大子序列和，注意，不是连续递增最大子序列和问题
int max_subsequence_sum() {
    int this_sum, max_sum, j;

    this_sum = max_sum = 0;
    for (j = 1; j <= n; j++) {
        this_sum += a[j];
        if (this_sum > max_sum)
            max_sum = this_sum;
        else if (this_sum < 0)
            this_sum = 0;
        else
            cout << "no action" << endl;
    }
    return max_sum;
}

int main() {
    //输入+输出重定向
    freopen("../1281.txt", "r", stdin);

    //动态规则(记录了最大值的DP表)

    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
    }
    for (int i = 1; i <= n; i++) {
        f[i] = a[i];
        for (int j = 1; j < i; j++) {
            if (a[j] < a[i] && f[j] + a[i] > f[i]) {
                f[i] = f[j] + a[i];
            }
        }
    }
    //输出dp表
    int maxx = INT32_MIN;
    for (int i = 1; i <= n; i++) {
        if (f[i] > maxx) maxx = f[i];
    }
    cout << maxx << endl;

    //关闭文件
    fclose(stdin);
    return 0;
}