#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;


}

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