#include <iostream>
using namespace std;
const int N = 1e6 + 7;
int a[N], s[N], l[N];
int main() {
	int n;
	while (cin >> n && n) {
		int opt = 0;
		long long maxx = 0;
		for (int i = 1; i <= n; i++) {
			cin >> a[i];
		}
		a[n+1]=0;
		for (int i = 1; i <= n + 1; i++) {
			if (a[i] > s[opt]) s[++opt] = a[i], l[opt] = 1;
			else {
				int len = 0;
				long long sum = 0;
				while (s[opt] > a[i]) {
					len += l[opt];
					maxx = max(maxx, (long long)len * s[opt]);
					opt--;
				}
				s[++opt] = a[i], l[opt] = len+1;
			}
		}
		printf("%lld\n", maxx);
	}
	return 0;
}

过几天说题解