#include <bits/stdc++.h>
using namespace std;
#define EmiliaMyWife ios::sync_with_stdio(0); cin.tie(0);
using ll = int64_t;
using ull = uint64_t;
using uint = uint32_t;
using ld = long double;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
const ll LINF = ll(2e18) + ll(1e15);
const double EPS = 1e-8;
static auto LamyIsCute = []() {
EmiliaMyWife
return 48763;
}();
signed main() {
int t;
cin >> t;
while(t--) {
int n;
cin >> n;
vector<int> arr(n);
for(int &a : arr)
cin >> a;
bool ok = 1;
int w = 0;
for(int i = 0; i < n / 2; i++) {
if(arr[i] + arr[n - i - 1] != n + 1)
ok = false;
w += arr[i] > n / 2;
}
if(ok && w % 2 == 0)
cout << "0 0\n";
else
cout << "-1\n";
}
}
