#include<iostream>
using namespace std;
  int suma( int x[], int i, int j)
 {
    int v1, v2, s=0;
     if(i==j) return x[i];
    else
    {
        v1=suma(x, i, (i+j)/2);
         v2=suma(x, (i+j)/2+1,j);
         if(v1%2==0 && v2%2==0) return s=v1+v2;
        if(v2%2==0) return s=s+v2;
         if(v1%2==0) return s=s+v1;
    }
}

int main()
{
    int a[1002], i, n;
    cin>>n;
     for(i=1;i<=n;i++) cin>>a[i];
    cout<<suma(a,1,n);
    return 0;
}