#include <fstream>
#include <cmath>
#include <vector>
#include <utility>
#include <algorithm>
using namespace std;

int i, a[100010], suma, n;
int main()
{

    ifstream fin("twoton.in");
    ofstream fout("twoton.out");
    fin>>n;
    for(i = 1; i <= n; ++i)
    {
        fin>>a[i];
    }
    suma = 1;
    for(i = n; i > 1; --i)
    {
        if(a[i] < a[i - 1])
        {
            a[i - 1] = a[i];
            suma = suma * 2 + 1;
        }
        else
        {
            suma = suma + 1;
        }
    }
    fout<<suma;
    return 0;
}