#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n; 
    scanf("%d",&n);    
    int *calories = malloc(sizeof(int) * n);
    for(int calories_i = 0; calories_i < n; calories_i++){
       scanf("%d",&calories[calories_i]);
    }
    
    long int result = -1;
    long int tmp;
    int j;
    for (int k = 0; k < n; k++)
    {
        tmp = 0;
        j = k;
        for (int i = 0; i < n; i++)
        {
            if (j == n)
                j = 0;
            tmp += (calories[j] * pow(2, i));
            j++;
        }
        if (result == -1 || tmp < result)
            result = tmp;
    }
    printf("%ld", result);
    return 0;
}