#include <iostream>

#include <cmath>

using namespace std;

int N;

int h[100001];

int seg[400004];

int init(int index, int start, int end) {

if(start > N) return -1;

if(start == end) return seg[index] = start;

int middle = (start+end)/2;

int leftIndex = init(2*index, start, middle);

int rightIndex = init(2*index+1, middle+1, end);

if(leftIndex == -1) return seg[index] = rightIndex;

if(rightIndex == -1) return seg[index] = leftIndex;

if(h[leftIndex] < h[rightIndex]) return seg[index] = leftIndex;

else return seg[index] = rightIndex;

}

int minIndex(int index, int start, int end, int left, int right) {

if (start >= left && end <= right) {

return seg[index];

}

if (start > right || end < left) {

return -1;

}

int middle = (start + end) / 2;

int leftIndex = minIndex(2 * index, start, middle, left, right);

int rightIndex = minIndex(2 * index + 1, middle + 1, end, left, right);

if (leftIndex == -1 && rightIndex == -1) return 0;

if (leftIndex == -1) return rightIndex;

if (rightIndex == -1) return leftIndex;

if (h[leftIndex] < h[rightIndex]) return leftIndex;

return rightIndex;

}

int maxArea(int left, int right) {

int index = minIndex(1, 1, pow(2, ceil(log2(N))), left, right);

int area = h[index] * (right - left + 1);

if (index - 1 >= left) {

area = max(area, maxArea(left, index - 1));

}

if (index + 1 <= right) {

area = max(area, maxArea(index + 1, right));

}

return area;

}

int main()

{

ios::sync_with_stdio(0);

cin.tie(0);

int i;

cin >> N;

for(i=1; i<=N; i++){

cin >> h[i];

}

int last = pow(2, ceil(log2(N)));

init(1, 1, last);

cout << maxArea(1, N);

return 0;

}