#include<iostream>
#include<fstream>
using namespace std;

ifstream f("twoton.in");
ofstream g("twoton.out");

int main() {
	int n;
	f >> n;
	int * numbers = new int[n];
	for (int i = 0; i < n; ++i) {
		f >> numbers[i];
	}
	int currentMin = numbers[n - 1];
	int result = 0;
	for (int i = n - 1; i >= 0; --i) {
		if (currentMin > numbers[i]) {
			result += 1;
		}
		else {
			result = 2 * result + 1;
		}
	}
	g << result;
	f.close();
	g.close();
}