#include <iostream>
using namespace std;

const int N = 1001;

int n, a[N];

int ans = 0;

void dfs(int L, int R) {
	if(L > R)
		return;
	int p = L;
	for(int i = L + 1; i <= R; i += 1)
		if(a[i] < a[p])
			p = i;
	ans += (p - L + 1) * (R - p + 1) * a[p];
	dfs(L, p - 1);
	dfs(p + 1, R);
}

int main() {
	int n;
	cin >> n;
	for(int i = 1; i <= n; i += 1)
		cin >> a[i];
	dfs(1, n);
	cout << ans << endl;
}