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

int findbig(int *a, int n){
  
  int i;
  int big = -1;
  
  for(i = 0; i < n; i++){
    if(a[i] > big){
      big = a[i]; 
    }
  }
  return big;
}

void radixSort(int *a, int n){
  int i;
  int tmp[n];
  int digit = 1;
  int big = findbig(a, n);
  while (big / digit > 0){
      int count[10] = { 0 };
      for (i = 0; i < n; i++){
          count[(a[i] / digit) % 10]++;
      }   
      for (i = 1; i < 10; i++){
          count[i] += count[i - 1];
      }
      for (i = n - 1; i >= 0; i--){
          tmp[--count[(a[i] / digit) % 10]] = a[i];
      }
      for (i = 0; i < n; i++){
          a[i] = tmp[i];
      }
      digit *= 10;
   }
}

int main(){
    int n; 
    int i = 0;
    long int dist = 1;
    long int miles = 0;
    scanf("%d",&n);
    int *calories = malloc(sizeof(int) * n);
    for(int calories_i = 0; calories_i < n; calories_i++){
       scanf("%d",&calories[calories_i]);
    }
    radixSort(calories, n);
    i = n-1;
    while (i >= 0){
        miles += calories[i] * dist;
        dist *= 2;
        i--;
    }
    printf("%ld", miles);
    return 0;
}