#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */  
    int n;
    cin>>n;
    int arr[n];
    for(int i=0;i<n;i++){
        cin>>arr[i];
    }
    for(int i=1;i<n;i++){
        int j;
        int temp=arr[i];
        for(int j=i-1;j>=0&&arr[j]>temp;j--){
            arr[j+1]=arr[j];
        }
        arr[j+1]=temp;
    }
    int count=0;
     int j=0;
     for(int i=n-1;i>=0;i--){
        
        count=count+(arr[i]*pow(2,j));
         j++;
    }
    cout<<count<<endl;
    return 0;
}