

import java.util.Scanner;
public class Maina
{
public static void main (String[]args)
{
Scanner db=new Scanner (System.in);
int a=db.nextInt();
int arr[]=new int [a];
int wee[]=new int [a];
int cou=0;
for(int i=0; i<a; i++)
arr[i]=db.nextInt();
boolean b=true;
while(b)
{
wee[a-1]=arr[0]/2;
for(int i=1; i<a; i++)
wee[i-1]=arr[i]/2;
for(int i=0; i<a; i++)
{
arr[i]=arr[i]/2+wee[i];
if(arr[i]%2!=0)
{
arr[i]++;
cou++;}
}
for(int i=0; i<a-1; i++)
{
if(arr[i]!=arr[i+1])
break;
if(i==a-2)
b=false;
}
}
System.out.println(cou);
}
}