#include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <cmath>
#include <unordered_map>

using namespace std;
#define ll long long
#define nl endl
#define cy cout << "YES\n"
#define cn cout << "NO\n"
#define sz s.size()

void sherry()
{
    ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
#endif
}
int main()
{
    sherry();
    ll n, sum = 0, c = 0;
    cin >> n;
    vector<ll> v(0);
    for (int i = 0; i < n; i++)
    {
        ll num;
        cin >> num;
        if (num > 0 && num % 2 == 0)
        {
            sum += num;
        }
        else if (num % 2 != 0)
        {
            v.push_back(num);
            if (num > 0)
            {
                c++;
            }
        }
    }
    sort(v.begin(), v.end(), greater<ll>());
    if (c % 2 == 0)
    {
        c--;
    }
    for (int i = 0; i < v.size(); i++)
    {
        sum += v[i];
        c--;
        if (c <= 0)
        {
            break;
        }
    }
    cout << sum;
}