#include <bits/stdc++.h>
//#include "grader.h"
#define respagold ios_base::sync_with_stdio(0), cin.tie(0);
#define int long long
#define ll long long
#define int2 __int128_t
#define FOR( i, x, n, d ) for( int i = x; i <= n; i += d )
#define FORR( i, x, n, d ) for( int i = x; i >= n; i -= d )
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x.size())
#define pb push_back
#define ins insert
#define lb lower_bound
#define ub upper_bound
#define pii pair <int, int>
#define mkp make_pair
using namespace std;
const int N1 = 2e5 + 123;
int a[N1], b[N1], c[N1], n, m, k, z, w, ans, x, y, pos[N1];
vector <pii> v;
mt19937 rng( chrono::steady_clock::now().time_since_epoch().count());
int rand( int l, int r )
{
uniform_int_distribution <int> uid( l, r );
return uid( rng );
}
void swp( int i, int j )
{
swap( pos[a[i]], pos[a[j]] );
swap( a[i], a[j] );
}
void solve()
{
cin >> n;
v.clear();
k = 0;
FOR( i, 1, n, 1 ) cin >> a[i], b[i] = 0;
FOR( i, 1, n, 1 )
{
if( a[i] != n - a[n - i + 1] + 1 )
{
cout << "-1\n";
return;
}
}
FOR( i, 1, n, 1 )
{
pos[a[i]] = i;
if( i <= (n >> 1) && a[i] > a[n - i + 1] ) k ++;
}
if( k % 2 )
{
cout << "-1\n";
return;
}
FOR( i, 1, n >> 1, 1 )
{
int ps = pos[i];
if( ps == i || ps == n - i + 1 ) continue;
int i1 = i, j1 = ps, i2 = n - i + 1, j2 = n - ps + 1;
v.pb({ i1, j1 }), swp( i1, j1 ), swp( i2, j2 );
}
vector <pii> po;
FOR( i, 1, n >> 1, 1 )
{
if( a[i] > a[n - i + 1] ) po.pb({ i, n - i + 1 });
}
FOR( i, 0, sz(po) - 1, 2 )
{
v.pb({ po[i].F, po[i + 1].S });
v.pb({ po[i].F, po[i + 1].F });
}
cout << sz(v) << ' ' << sz(v) << '\n';
for( auto i : v ) cout << min( i.F, i.S ) << ' ' << max( i.F, i.S ) << '\n';
}
signed main()
{
// freopen("connect.in", "r", stdin);
// freopen("connect.out", "w", stdout);
respagold
int test = 0;
if( !test ) cin >> test;
while( test -- )
{
solve();
}
}
// solved by KluydQ
