#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main() {
    int t;
    cin>>t;
    while(t--) {
        long n,p=0,q=0;
        long sum1=0,sum2=0,sum3;
        vector<long> v1,v2;
        long x;
        for(long i=0;i<n;i++) {
            cin>>x;
            if(x>0) {
                v1.push_back(x);
                p++;
            }
            else {
                v2.push_back(x);
                q++;
            }
        }
        sort(v1.begin(),v1.end());
        sort(v2.begin(),v2.end());

        while(p>=0 && q>=0)  {

        v1.pop_back();
         p--;


        v2.pop_back();
         q--;

        }
              if(p<0) {
                  p = 0;
              }
              if(q<0) {
                  q = 0;
              }
        for(long i=0;i<p;i++) {
            sum1+=v1[i];
        }
        for(long i=0;i<q;i++) {
            sum2+=v2[i];
        }
        sum3 = sum1 + sum2;
        cout<<sum3<<endl;
    }
    return 0;
}