import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNextInt()) {
int n = sc.nextInt();
int[] nums = new int[n];
for (int i = 0; i < n; i++) nums[i] = sc.nextInt();
int[] dp = new int[n];
for (int i = 0; i < n; i++) dp[i] = nums[i];
for (int i = 1; i < n; i++) {
for (int j = 0; j < i; j++) {
if (nums[j] < nums[i]) dp[i] = Math.max(dp[i], dp[j] + nums[i]);
}
}
int max = 0;
for (int x : dp) if (x > max) max = x;
System.out.println(max);
}
}
}