#include <iostream>
using namespace std;
int main()
{
int n,x,v[100],S1,S2,i;
x=0;
cin>>n;
while(x<n)
{
cin>>v[x];
x++;
}
x=0;
while(x<n)
{
S1=0;
S2=0;
i=0;
while(i<x)
{
S1+=v[i];
i++;
}
i=x+1;
while(i<n)
{
S2+=v[i];
i++;
}
if(S1==S2)
cout<<v[x];
x++;
}
return 0;
}