// Online Java Compiler
// Use this editor to write, compile and run your Java code online
import java.util.*;
class HelloWorld {
public static long getMinimumMoves(List<Integer> quantity){
long sum=0l;
for(int i:quantity){
sum+=(long)i;
}
long half = sum/2, s=0l;
for(int i=0;i<quantity.size();i++){
s+=(long)quantity.get(i);
if(s>half){
if(i==0 || i==quantity.size()-1) break;
return s-(sum-s);
}else if(s==half){
return 0;
}
}
if(quantity.get(quantity.size()-1)>half){
return 2l*(long)quantity.get(quantity.size()-1)-sum;
}
return (long)quantity.get(quantity.size()-1)-(sum-(long)quantity.get(0));
}
public static void main(String[] args) {
List<Integer> quantity = new ArrayList();
quantity.add(3);
quantity.add(3);
quantity.add(6);
quantity.add(3);
quantity.add(9);
System.out.println(getMinimumMoves(quantity));
}
}