C

#include <bits/stdc++.h>

using namespace std;

#define pb     push_back
#define _test   int _TEST; cin>>_TEST; while(_TEST--)

int main()
{
    _test
    {
        int n;
        cin>>n;

        vector<int> a(n);
        for(auto &e: a)     cin>>e;

        vector<int> b, c;

        for(auto e: a)
        {
            if(e%2)     b.pb(e);
            else        c.pb(e);
        }

        if(b.size()%2)
        {
            cout<<-1<<"\n";
            continue;
        }

        vector<int> ans(n);
        int pos = 0;

        sort(b.rbegin(), b.rend());
        sort(c.rbegin(), c.rend());

        for(int i=0; i<b.size()/2; i++)
        {
            int x = b[i] + b[b.size()-i-1];
            x /= 2;
            ans[pos] = x;
            ans[pos+n/2] = b[i]-x;
            pos++;
        }

        for(int i=0; i<c.size()/2; i++)
        {
            int x = c[i] + c[c.size()-i-1];
            x /= 2;
            ans[pos] = x;
            ans[pos+n/2] = c[i]-x;
            pos++;
        }

        for(auto e: ans)
            cout<<e<<" ";
        cout<<"\n";
    }
}