#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>Set;
typedef tree<ll,ll,less<ll>,rb_tree_tag,tree_order_statistics_node_update> Map;

#define pb push_back
#define mp make_pair
#define mod 1000000007
#define fi first
#define se second
#define pll pair<ll,ll>
#define ook order_of_key
#define findby find_by_order
#define pii pair<ll,ll>
#define gcd(a,b) __gcd(a,b)
#define rep(i,n) for(ll i=0;i<n;i++)
#define reps(i,a,b) for(ll i=a;i<=b;i++)

template<typename X> inline X abs(const X& a) { return (a < 0 ? -a : a); }
template<typename X> inline X sqr(const X& a) { return (a * a); }

const ld EPS = ld(1e-9);
const ld PI = ld(3.141592653589);

int n;
int s[100005];

class Task
{
public:
     void solve(istream& in,ostream& out)
     {
          in >> n;

          vector <int> pe,po,ne,no;

          rep(i,n)
          {
                in >> s[i];
                if (s[i] % 2 == 0)
                {
                     if (s[i] <= 0)
                     {
                          ne.pb(s[i]);
                     }
                     else
                     pe.pb(s[i]);
                }
                else
                {
                     if (s[i] <= 0)
                     no.pb(s[i]);
                     else
                     po.pb(s[i]);
                }
          }

          int res = -2;
          if (po.size()>0)
          sort(po.begin(),po.end(),greater<int>());

          if (po.size() % 2 == 0 && po.size() != 0)
          {
                res = 0;
                rep(i,po.size()-1)
                {
                     res += po[i];
              //       out << po[i] << endl;
                }
          }
          else if (po.size() % 2 == 1)
          {
                res = 0;
                rep(i,po.size())
                {
                     res+=po[i];
           //          out <<po[i] <<" hsgd" << endl;
                }
          }

          if (res == -2)
          {
                res = 0;

                if (no.size()>0){
                     sort(no.begin(),no.end());

                     res += no[no.size()-1];
                }
          }

          rep(i,pe.size())
          {
                res += pe[i];
     //           out <<pe[i] << endl;
    //            out << "sdhas" << endl;
          }

          out << res << endl;

    //      out << (3 & 1) << endl;
     }
};


int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    Task solver;
    std::istream& in(std::cin);
    std::ostream& out(std::cout);
    solver.solve(in,out);
    out.flush();

    return 0;
}