import java.util.Scanner;
import java.util.Stack;

public class Main2{
    public static int Rect(int[] a){
        int r = 0;
            int area;
            int vt;
            Stack<Integer> s = new Stack<>();
            int i = 0;
            while(i < a.length){
                if(s.empty() || a[s.peek()] <= a[i]){
                    s.push(i++);
                }
                else if (!s.empty()){
                    vt = s.peek();
                    s.pop();
                    area = a[vt] * (s.empty() ? i : i - s.peek() - 1);
                    r = Math.max(r, area);
                }
            }
            while(!s.empty()){
                vt = s.peek();
                s.pop();
                area = a[vt] * (s.empty() ? i : i - s.peek() - 1);
                r = Math.max(r, area);
            }
            return r;
    }
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while(true){
            int n = sc.nextInt();
            if (n == 0) break;
            int[] a = new int[n];
            for (int i = 0; i < n; i++) {
                a[i] = sc.nextInt();
            }
            System.out.println(Rect(a));
        }
    }

}