#include <bits/stdc++.h> #define pb push_back #define ll long long #define fi first #define se second using namespace std; vector<int>v,vv;int n; vector<pair<int,int>>w; int a[1000000]; int main() { int t;cin>>t; while(t--) { int n; cin>>n;int re=0; for(int i=1;i<=n;i++)cin>>a[i]; for(int i=1;i<=n;i++) { if(a[i]==i)continue; for(int j=i+1;j<=n;j++) { if(a[j]==i) { re++; w.pb({i,j}); swap(a[i],a[j]); swap(a[n-i+1],a[n+1-j]);break; } } } for(int i=1;i<=n;i++)if(a[i]!=i)re=-1; if(re==-1) { cout<<-1<<endl;w.clear();continue; } cout<<0<<" "<<w.size()<<endl; for(auto it:w) if(it.fi==it.se)continue; else cout<<it.fi<<" "<<it.se<<endl; w.clear(); } }