#include <bits/stdc++.h>
#include<iostream>
using namespace std;

int main(){
    int n,i,k,j;
    long int s;
    cin >> n;
    int a[n];
    for (i=0;i<n;i++)
        cin>>a[i];
    for (i=0;i<n;i++)
        for (j=i+1;j<n-i-1;j++)
        if (a[j]>a[j+1])
        {
        k=a[j+1];
        a[j+1]=a[j];
        a[j]=k;
    }
    for (i=n-1;i>=0;i--)
        s=s+a[i]*pow(2,(n-1-i));
cout<<s;
    
    
    // your code goes here
    return 0;
}